You can get it here: http://www.microsoft.com/downloads/en/details.aspx?FamilyID=11ea69cb-cf12-4842-a3d7-b32a1e5642e2
The installer covers all editions of Visual Studio 2010 – Express, Professional, Premium, & Ultimate. The what’s new covers some of the benefits of SP1, but here is a consolidated list:
Unit Testing (now includes SharePoint 2010)
You can run unit tests that target the .NET Framework 3.5 from Visual Studio 2010 SP1 Beta on your local machine.
You can run unit tests that target the .NET Framework 3.5 by using MSTest.exe from the command prompt.
You can run unit tests on a build agent as part of a build.
IIS Express - a lightweight Web server that you can use in Visual Studio. IIS Express combines the simplicity of the ASP.NET Development Server with many powerful Web server features offered by IIS 7.5. IIS Express offers the following advantages:
It is less than 10 MB, and it consumes fewer system resources than IIS 7.5.
It works in Visual Studio 2010 and in Visual Web Developer 2010 Express.
You do not have to use an administrator account to run or debug Web applications in Visual Studio.
Most development features available for IIS 7.5 are available for IIS Express.
SQL Server Compact 4.0 Design Time Support - an embedded database server that has a small footprint. The Visual Studio 2010 SP1 Tools for SQL Server Compact 4.0 CTP2 enable you to work with SQL Server Compact databases in Visual Studio Web projects.
Using SQL Server Compact databases and tools provides the following advantages over using the full SQL Server or SQL Server Express edition:
They are quick to install and set up. The total download for the database and tools is less than 20 MB.
Data storage is file based. Your data is stored in a single .sdf file, which you can copy to the App_Data folder of your ASP.NET application on a Web hosting site.
Database deployment is improved. Transact-SQL and .NET Framework data APIs are compatible. You can use the same SQL commands and database code that you use with other versions of SQL Server.
Visual Studio design-time data tools, such as Server Explorer, the Query and View Designer, the Entity Designer, the SqlDataSource control, and the Dataset Designer, all work with SQL Server Compact databases.