Governance Over Customizations
Speaking of code, the Developer Dashboard lets administrators and developers monitor the impact of customizations on pages. The Dashboard can be exposed on a page to reveal performance and debugging information.
Any custom code has the potential to affect other processes and system resources on a SharePoint farm. The Developer Dashboard provides insight for monitoring and debugging, but real control is exerted by deploying sandboxed solutions. Using sandboxed solutions, deployed as SharePoint solutions (.wsp) packages that can touch a limited set of APIs, you can isolate custom code to prevent it from affecting other processes, and to control the resources that can be consumed. You can delegate the ability to upload custom user code to site admins with the confidence that any problems won't harm other apps or the farm. Site admins can also be delegated the ability to monitor and deactivate the feature that enables the problematic custom code.
In addition to controlling custom code, SharePoint 2010 gives you control over other customizations, including look-and-feel changes such as themes and customizations made using SharePoint Designer 2010.Unfortunately, the benefits of developing for and customizing SharePoint using Visual Studio 2010 and SharePoint Designer 2010 apply only when those applications are used against SharePoint 2010. In fact, you must use previous versions of Visual Studio and SharePoint Designer to code for and customize SharePoint 2007. If your enterprise includes mixed levels of farms, you'll need to support both customization and development environments. This fact alone might make you want to upgrade the entire enterprise to SharePoint 2010 as quickly as possible.
Governance Over Client Integration
Office 2010 client applications provide additional functionality when paired with SharePoint 2010. While Word, PowerPoint, Excel, Access, Outlook, Project, and OneNote continue to improve their already strong SharePoint integration, specific applications, such as SharePoint Workspaces (formerly known as Groove), SharePoint Designer, and InfoPath, will see increased use and might be entirely new to your organization. When your users discover what they can do with these applications, your governance plan had better explain when these applications will be supported.
SharePoint 2007 let you enable or disable all client integration with a single switch. SharePoint 2010 adds granularity. At the list or library level, you can enable or disable Microsoft Office client integration features.
Extended Browser Support
In some ways, IT pros have it easy with SharePoint 2007. Users can access SharePoint only through Internet Explorer, and some of my clients have used that fact as an excuse to prohibit installation of Firefox, Safari, and other browsers. The good news is that SharePoint 2010 supports Firefox and Safari, as well as other browsers and devices. The bad news is that now you might be asked to support those browsers.
List and Library Scalability
Microsoft has improved the experience with lists and libraries in SharePoint 2010, which now supports lists and libraries with millions of items. Changes to both the back end (with improved SQL Server queries) and the front end (how web front-end servers retrieve and present list and library content) make a world of difference by balancing the end-user experience with the impact on the server infrastructure.
On the server side, you can configure Web application settings that control the maximum number of items returned by a query generated by a list or library view; the default is 5,000 items. You can set different limits for administrators and nonadministrative users. When a view generates a number of items greater than this limit, a warning message appears at the top of the list informing the viewer that the view isn't returning all items. Additionally, a warning appears on the List Settings page.
Web application settings let you set what is oddly called the Happy Hour window—a period of time each day during which query limits aren't applied. You set the window to start at a specific time each day, seven days a week, to run for a whole number of hours. Both the name and the lack of granularity of control qualify the Happy Hour window as a half-baked feature.
When it's not Happy Hour, views won't return more items than the query limit, but SharePoint 2010 makes it easy to help users dynamically filter data to narrow the result set. Metadata can be used to create a navigation hierarchy and content filters. The result is a tag-based folder hierarchy, using keywords or metadata, that filters the result set and therefore narrows the number of items returned.
Farm Service Scalability
Service applications in SharePoint 2010 replace the Shared Services Provider (SSP) model of SharePoint 2007. Forget everything you know about SSPs. The new model is radically different, better, and easier.
SharePoint 2010 has several built-in services, including Business Data Connectivity, Visio Graphics Service, Excel Services, Office Web Apps, Search, User Profile, Web Analytics, and the new Managed Metadata Service, which creates a central store for taxonomy and content types. Each service runs as an application exposed as a Windows Communication Foundation (WCF) service on one or more application servers in the farm. Consumers such as web parts, typically on web front ends, utilize the service. To connect the consumer to the service, each service application has a proxy that knows how to talk to the service.
This architecture, which is completely extensible so that third parties can create new service applications, offers several advantages. First, a service can be published to other farms by installing the service application proxy on the other farm and pointing it to the Uniform Resource Identifier (URI) provided by Central Administration when you publish the service application. Therefore, farms can share service applications, providing unified services for functions such as search, taxonomy, data aggregation, and analytics.
Second, Web applications can be configured to use one or more instances of a service. For example, a Web application for a company's finance department can consume a taxonomy service (the Managed Metadata Service) that provides a taxonomy specific for finance and another service that provides a unified, enterprise-level taxonomy.
Third, services can be scaled up in times of high demand. If a service is in high demand, you can deploy the service application to additional application servers. When the service proxy queries the farm for the location of the WCF service, the service architecture returns the instance of the service in round-robin fashion, including the new application servers.
Another capability of service applications is multi-tenancy, which is used to partition a service so that it returns a subset of data. The classic use of this technique is for hosted SharePoint offerings where a single Search service is used by several hosted customers. Obviously, it's important that search results are restricted to each customer's data—that a security layer prevents leakage of search results. This security is achieved by implementing multi-tenancy, which adds a subscriber ID field to each row of data in the Search service. A site collection, which is specific to a customer, with that subscriber ID can return results only from the service that matches the subscriber ID. There will certainly be other services and other scenarios—even intranet scenarios—in which enterprises will want to partition the data returned by a single service application.
Wrapping It Up
This article has described many significant changes for IT professionals in SharePoint 2010. Microsoft groups these improvements into three categories: Increased Productivity, Scalable Unified Infrastructure, and Flexible Deployment. These high-level groupings obscure some of the most important and high-impact aspects of SharePoint 2010. I've tried to point out the features I think will be most welcome—or most half-baked—but only time will tell, after enterprises get SharePoint 2010 into production.