"After Google, What?" was the name of a course at the iSchool, but Paul Smith of EveryBlock has asked the same of Google Maps. His answer? An open source web mapping stack. Check out his cool article on A List Apart, "Take Control of Your Maps". If you haven't checked out EveryBlock, do so. Their maps are beautiful. We use a lot of these technologies in the lab and in the GIIF, with the exception of Mapnik, which, to my shame, I've tried and failed to install. Update Some responses: a thread on geowanking including a response from Google evangelist Pam Fox, and discussion and response from the author on ALA (for some reason the post isn't on Technorati yet...).