Hi! I'd like to introduce a project that I'm coordinating at the AtariAge.com forums. We're collectively trying to document all known cartridges for the Atari 8-bit computers (of all categories - Games, Applications, Demos, Operating systems). In the process we've managed to discover that quite a few of the known cartridge images are in fact cracks or bad dumps, and we've also verified some dumps as genuine.
Our effort's goal is mostly the same as TOSEC's. When updating the Atari 8-bit DATs, consider looking into our results. Link