This afternoon, Microsoft unveiled a slate of new enhanced releases, including an updated .NET Framework 3.5 SP1 that had been in beta only since February, and the first service pack for Visual Studio 2008 only six months after its premiere.

There was some early confusion today over just what "shrunk" in this latest slate of .NET Framework releases, but after going through the releases ourselves, we discovered what some Microsoft spokespersons meant to say in the beginning: The latest SP1 adds a new concept called the .NET Framework Client Profile, which enables an application's setup routine to include only those features it may require to serve as a .NET client, on a Windows platform where .NET Framework is not automatically installed -- for instance, XP SP2 or SP3, or Windows Server 2003. In short, it's a reduced profile for client-only applications that don't require the entire .NET to be distributed with them, and don't have the luxury of the entire .NET pre-installed.

That profile reduction, Microsoft now says, means that a reduction in redistributed code components of nearly 87%, to 26.5 MB.

"The Client Profile is streamlined to be focused 100% on Client Applications," Microsoft spokesperson Josh Rein told BetaNews this afternoon. ".NET Framework historically contained all components from service development, to client development, to server development, etc. in the core package. By removing the non-essential aspects for client [development], we were able to decrease the installation size."

As we discovered for ourselves this afternoon, the Framework itself has not shrunk. The full 3.5 SP1 package for application developers was a 231 MB package, with an additional 52 MB subsequent download. Meanwhile, the redistributable package, which contains the Common Language Runtime and the part those elements need to be executed, remains small at 2.8 MB.

Added to this service pack is a long-awaited feature that had been anticipated for SQL Server last year, called the Entity Data Model. Now considered a component of ADO.NET (the evolution of ActiveX Data Objects), it enables a new model for representing data that is more akin to object orientation than the typical table/record/entry breakdown.

Specifically, data items in an entity may now have complex properties. Those properties may themselves have structure, and the association between an entity and its properties forms a more direct relationship. For instance, in the old SQL model, there may be one table for an inventory item and another for a customer. A purchase order would be a list of third-order relationships that bind items of inventory to the customer who purchased them. In the new system, a purchase order entity may have a customer as its complex property.

The Entity model will also be used as an enhancement to ASP.NET Dynamic Data (related to ADO.NET, though not the same thing), a feature which was first previewed in a CTP last December. This enables developers to design database schemas on the fly using graphical representational models (like the one popularized in Microsoft Access), though which generate the underlying XML code automatically. This code will also now be generated for entities as well as the conventional model.

The ADO.NET Data Services Framework will follow up on this feature by applying the Representational State Transfer (REST) model, which is better suited to Web-driven databases. This model divides the users of a database into three departments. While the user directly interacts with a portlet, it is the intermediary consumer that transacts with the database server, or producer. This abstraction between the user of the data and the user of the database helps eliminate the tangles experienced when a complex database is distributed over the Web.

Being able to take advantage of these new features in programs is one of the key provisions of Visual Studio 2008 Service Pack 1, which was also released today. New "Designers" (code-building components) needed to be added for ADO.NET and ASP.NET AJAX to take advantage of the Entity model, as well as to improve overall reliability, and those new Designers were added to this latest release.

Another interesting feature of that new SP1 is the provision for something called the Visual Studio isolated shell. Essentially, it enables third parties to create custom-branded development environments that utilize the Visual Studio engine, and selected elements of its look and feel, though without having to represent itself as a VS knockoff.