Looks cool but if possible remove the dependence on ARC.
So it seems quite logical for developers to rely on most modern technologies, esp. since supporting older technologies comes with a cost.
Still, its not like I'm doing more work anyway, going with ARC saved time on development. If Apple ends up never releasing 4.2, I would just had to "finish" the job.
Looks like a cool library though! Once they manage to make Xcode 4.x work as well as Xcode 3.2, I will try it.
Have you tried AppCode, from JetBrains? Its still in beta, but its magnificent.