Q&A System For Tracking – Stack Overflow

I was just pointed to a new open community Q&A system for programmers – Stack Overflow at http://stackoverflow.com/. There is a xen tag and virtualization tag already in place so if you ask any Xen questions, please use the appropriate tags.
Sample Q&A – http://stackoverflow.com/questions/97188/is-there-a-monitoring-tool-like-xentop-that-will-track-historical-data.
Please note, the site is not about system administration, they are launching a sister site just for that, serverfault:

http://blog.stackoverflow.com/2009/04/server-fault-private-beta-begins/
Thanks to Tim Post  for the lead on StackOverflow.