ChinGav has investigated Ruby since late 2005 and hasn't looked back since. He has similarly switched to the Mac and investigated Mac programming in 2006 and hasn't regretted it at all, either. In short, RubyCocoa is a perfect match. He maintains a blog called Mac OS X coding∞ which talks about Cocoa, Ruby, RubyCocoa (among other topics). He also has a set of screencasts on Ruby at Showmedo∞.