Just added GameCenter support via OpenFeint 2.7i.
Just waiting for the rest of the higher res artwork for another 15 achievements to be done now before I can release the update.


OpenFeint Documentation took me a little while to find b/c the OFGameCenter.plist wasn't included in the sample code. After I inputted all the achievements and leaderboards into iTunesConnect, I only needed to change 1 line in my code and add a couple of frameworks.
The thing that took the longest was figuring out how to log into the sandbox version of Game Center to test. I've been using wild card app ids since the beginning so I needed create a new app id in the provisioning portal. Then once that was enabled, I have to sign the development binary with the profile. Even then, logging into the sandbox was intermittent, but I can't sure if it's a problem with my internet connection here or not. I ended up creating 3 new apple ids until I finally got one that worked.
And the final gotcha was that even though I signed with the new provision in xcode, it didn't actually take properly on the device until I manually deleted the old install from the device. Then it finally logged me into the sandbox.
Now that I think I've figured out how to integrate Game Center and test properly, it should be really quick for me to update all my games to use OF 2.7i along with Game Center support.
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re: 20mb 3G d/l limit
So I finally whittled it down to 19.7mb on iTunes and I want to say that sales seem to have gone up slightly, but I can't be sure it's because of the binary size. I found that having somewhat high quality JPG instead of PNG files saved me a ton of space with no visible artifacts. Because the app is universal, I included background images in PNG in 1024x768 which can sometimes take up to 1mb where as JPG files are less than 200kb.