Just a quick heads-up: iRealSMS pushed a beta update that brings support for iOS5. No real extra features were added right now, it’s a beta so expect bugs and they didn’t integrate notification center yet. But because of Apple’s implementation of iMessage, it took almost a complete rewrite of the iRealSMS app – and they only got one developer so be patient.
One cool thing about this beta is that, if installed, it will automatically replace messages.app. It doesn’t put a completely separate app on your SpringBoard anymore.
To test iRealSMS with iOS5 support add the following source in Cydia: http://www.irealsms.com/beta_repo/