You may want to take note that ESRI does not currently support ArcGIS products on Windows Vista and
does not have plans to add Vista support to ArcGIS product versions up
to and including 9.2.
This doesn't necessarily mean that it "won't" work, just that if you run into trouble, I will not be able to get a technical support response. And, note that there have been issues with the License Manager posted by users on ESRI's forums.
According to their web site, ESRI intends to add support for
Windows Vista in service packs released after ArcGIS 9.2 Service Pack
2, as well as future releases of ArcGIS products. But for now, if you are a hard core ArcGIS user and cannot risk technical difficulties, stay the course with XP.
Regarding other ESRI software, ArcView 3.x is not supported on the Microsoft Windows Vista
operating system and there are no plans to support ArcView GIS 3.x on
this operating system in the future.
All versions of ArcPad up to and including ArcPad 7.0 are not
currently supported on the Microsoft Windows Vista release, but ESRI intends to add support for Windows Vista in future
service packs and future releases.
PLEASE REFER TO BLOG ENTRY OF JANUARY 4, 2008 FOR AN UPDATE