I just created a new project in Xcode 4 and I guess I left the \"Create local git repository for this project\" box checked. Now, I would like to remove this version control
I had the same problem. I followed the steps from this blog post and all worked fine for me. I was using Xcode 4.2 on OS X 10.7.3.
I think the trick is making sure to delete the invisible ".git" folder in the project directory via the command line,... in addition to deleting the repositories via the Xcode GUI.
I'm now using SourceTree with Mercurial on BitBucket, and am a very happy camper! :-)