5) Personally I have dropped all .jpgs/.pngs from my game from the start... I want 100% quality where every pixel is like I want and does not detoriate during editing (saving, editing, saving etc .jpgs does that) and only .tga and .bmp formats can deliver that. Filesizes are bigger, yes, but in the end the difference isn't that great IMO (what's few megs anyway...). And of course .tgas and .bmps compress pretty nicely for installer/download package.