I may have missed this before, and if I have, I apologize (I searched and didn't find anything).
Is there a way to discover what the API version for a site is? With the recent change from 0.8 to 0.9, there's been some whining about having to change code and whatnot. Could we mitigate this issue in the future by making the version discoverable?
I think a good place to put this would be the http://stackauth.com/sites endpoint, where each site could now include a
"version": "0.9" entry.