Saw this over at Pocket Gamer. Yoyo games apparently has a PC game creation program called Gamemaker, and are apparently porting the engine that runs the games to the PSP.
They have a video of it here
http://glog.yoyogames.com/?p=829
Sounds like they intend for it to be an official product. Either standalone, or perhaps games could be released separately as Minis. Interesting at any rate
PSP games will have to be submitted to YoYo games to get onto PSP, though we will release a product allowing you to see how games will run on the PC (and have the same restrictions as the PSP version).