Just noted @spolsky tweet "Stack Exchange of the day" http://ask.sqlservercentral.com clearly focusing on SQL server.
I also discovered http://uxexchange.com/ focusing on User Experience issues.
I suspect there may be more Stack Exchange based sites with a more tightly focused programming related subject area and more to come. Which is great for those guys that own Stack Exchange.
However now if I have a SQL server question where do I ask? Stack Overflow or ask.sqlservercentral.com? What happens if someone builds a CSharpExchange, JavaExchange etc?
Bottom line, is this proliferation going to dilute and ultimately undermine the benefit of Stack Overflow?