Actually this works just fine - ICOCA can charge Suica and v/v... but as you note, Suica doesn't work on most of the useful systems in Kansai (Osaka subway, Nankai line, etc.) until the Grand Unification in 2013 of most of the remaining IC systems.

Personally, I'm happy that basically my Suica works anywhere but Kansai and Nagoya private lines at this point... I've used my Suica for a bus in Fukuoka and a train in Sapporo already this year.