On multiple ROM's now I've noticed the Market just randomly forgets up to 1/2 of what I have installed until I clear data in settings/applications. It usually forgets again after a reboot or just randomly. It seems like this is a Google server issue since I have it happen on multiple ROM's but I just want to be sure. On a fresh install of Sapphire it just did it to me again, though not as bad only about 5 apps missing.