If you want to keep up to date with information on new releases of mtPaint you are advised to subscribe to the announce mailing list:http://lists.sourceforge.net/lists/listinfo/mtpaint-announce
If you are a user of mtPaint and you want to give feedback, you are welcome to post a message to the user mailing list:http://lists.sourceforge.net/lists/listinfo/mtpaint-user
I am happy to receive constructive emails relating to bug reports, feature suggestions or contributions of translations to new languages. Please be aware that mtPaint is developed in my own spare time. Therefore I may have to refuse feature suggestions if they don't conform to my general vision for mtPaint or would require too much effort for too little gain.
If you are a developer and you have improved any part of mtPaint you are welcome to post a message to the developers mailing list:http://lists.sourceforge.net/lists/listinfo/mtpaint-devel
If you want to help with testing new features, subscribe to the developers mailing list too, because it is where releases of intermediate alpha versions will be announced.
I would also be happy to hear from you if you have used mtPaint (or any part of it) in your own work, either as an artistic tool or some other use (e.g. including mtPaint in an operating system, or using code fragments from the mtPaint sources).
If you would rather contact me directly you can send an email to firstname.lastname@example.org