Saw a weird bug in VSTO this weekend as I was setting up a new home machine (Quad core—woohoo!). After I installed VSTO, I got this in the new projects dialog:
Version2003 and Version2007 were displayed rather than 2003 and 2007.
Turns out that this can happen if you install Vista, then install Visual Studio, then install Vista SP1—which I did.
The fix for this if you want to get back to the expected 2003 and 2007 labels is to launch the Visual Studio Command Prompt and run devenv.exe /setup which will reset the labels.