VS2008 hasn't even been fully launched yet and already the add-ons are becoming available through the VSTS 2008 Power Tools. These power tools are very handy and also offer some bugfixes so you don't have to wait for a service release.

New in this release of the power tools:

• Find in Source Control tool is an addition to the Team Explorer menu that provides the ability to locate files and folders in source control by the item’s status or with a wildcard expression.
• Open a selected folder in Windows Explorer straight from Team Explorer. This feature allows you to jump straight to the mapped folder location from within Source Control Explorer.
• Quick Label feature that allows labels to be easily applied to a given selection of files and folders in the Source Control Explorer.
• Build Notification tool that runs in the Windows task bar notification area monitoring the status of the build definitions you have specified. It can be configured to show notifications when builds are queued, started, or completed for multiple build definitions spanning multiple Team Foundation Servers.
• Additional TFPT.EXE commands for configuring Team Explorer connection settings (tweakui) and for  destroying Work Items and Work Items Type Definitions (destroyWI, destroyWITD).
• Updates to the TFS Best Practices Analyzer for use with a Visual Studio Team System 2008 Team Foundation Server deployment.
• The Process Template Editor is updated for use with Visual Studio Team System 2008 Team Foundation Server. It also has several improvements, including: the ability to launch standalone w/o a Visual Studio installation, performance improvements, improved discoverability and bug fixes.
• Bug fixes and removal of Power Tools that are now included within Team Foundation Server: 
  • Annotate and Treedif are now included in Visual Studio Team System 2008 Team Explorer; however, Annotate remains is still available in the command-line tool (TFPT.EXE).
  • TestToolsTask is included in Visual Studio Team System 2008 Team Foundation Server as part of Team Foundation Build.

With certifications like 70-620 and 70-291 on ones credit, one can easily go for 646-171. In fact, even 642-825 is not difficult for such people. However, exams like 640-863 and 350-001 require much more preparation time and effort, than that required for a basic exam like 1z0-042.