I have been exploring Visual Studio 2010 for some time now. While lots of new features have been introduced, there are a number of areas where Visual Studio 2010 shows marked improvement compared to its earlier counterparts.

One of the major improvements in Visual Studio 2010 IDE is in the 'Add Reference Dialog'. The Add Reference Dialog is used to add .NET assemblies or components into your existing project. The major drawback of the Add Reference Dialog in the earlier versions of Visual Studio is its slow performance due to the synchronous scan of the .NET Global Assembly Cache to retrieve the assembly information and then populate the list of the ready-to-add .NET assemblies.

Note that GAC scan was done using the User Interface thread in the earlier versions of Visual Studio. This resulted in slow responsiveness as GAC scan often takes a lot of time and you have had to wait for quite some time for the dialog to respond. In essence, the major bottleneck in the Add Reference Dialog in the earlier versions of Visual Studio was that you were constrained to wait until the scan was complete before the Add Reference Dialog would respond again. The Global Assembly Cache is a central location in your system where the .NET assemblies are stored. Such assemblies also have globally unique identifiers called string names. This is the reason why these assemblies are also called strong named assemblies.

With Visual Studio 2010 things have changed. In Visual Studio 2010, the .NET and COM tabs now load asynchronously and as a result, the User Interface thread is not blocked while the list of the ready-to-use assemblies and components is being populated. So, now you can switch between tabs in the Add Reference Dialog (as they no longer load synchronously) without having to wait for long.