Shuhei Yoshida from Sony reported a news on Edge Magazine via CVG m he told us PS3 game ports to NGP (Next Generation Portable) will be both simple and quick for players.
Here is the quote: Today, many teams are familiar with the PS3 and are used to including a variety of effects in their titles.
"Based on this expertise - and also the working habits they developed working on the PS3 - we had to make development on the NGP as natural as possible - an extension of the PS3, if you will.
"So the three demos you've seen - Lost Planet 2, Ryu Ga Gotoku [Yakuza] and MGS4 - they prove porting is simple and quick, but it doesn't mean that's all you can expect. My view of NGP isn't just as a platform for porting PS3 titles."
Source: CVG site