I released a new version of Lunapaint today. My app is now at version 0.2.6. The main features are PNG export and a new GUI rewamp. There haven't been too many bug fixes though, so the bugs that were discovered in 0.2.5 should still be in here, except for the showstoppers which leads to a crash.
Anyway, now that Cristophe has committed himself to Wanderer I thought I'd use some more time on Lunapaint to get it to version 0.3. There aren't that many things left, and it should mostly be about closing some bugs and adding polish. With bugs in mind, I set up a forum at:

http://www.sub-ether.org/phpBB2/

Please use this forum to post your experiences and bug reports. Other than that, paint pretty pictures and have fun!