I've made an auto-updater plugin which will be somewhat useful after a 1.0 release.
Basically it checks for a new build on the Github 'master' and (if you want it to) downloads and replaces the current Paint.JAVA installation with the new file.
Due to issues with development builds, if it detects you are using the latest build from the 'dev' branch, it ignores any update.
At the moment, it's quite useless, as there's only one stable version that's compatible, so it can't update anyway.
(Ninja-Edit: Due to a hotfix, now there are two stables. Still doesn't make a difference though)
Anyway: Paint.JAVA Auto-Updater on GithubAlso, I pushed out v1.0-Beta.2
Features lots of minor tweaks, a 'colour square' (courtesy of BurntPizza) for the colour picker (it looks a bit awkward, but I'll fix it soon)
Please report any bugs you find.