Having only purchased this game recently, I am already addicted to it! It really is an awesome game, however I didn’t buy it for the iPhone (I own a Droid) or for the iPad (Still deciding if I should get one). No I bought it for my laptop, and while it is mobile, it doesn’t very well fit into my pocket.
The blogosphere is afire with news that Sony maybe working on a successor to the PSP, and that it will have touch controls on the back (Kinda like the Motorola phone with the pad on the back.), this could be big news if its true. One other thing is that the size will probably be the same, with just the touch controls placed on the back and likely to use the same UMD format as now, likely not following the PSP-Go method of buying games.
The source told Eurogamer that they expect it to be released at the end of 2011, no doubt shortly before Christmas and likely to be announced at E3 2011, if this news is true.