Struggling to get into this game. Missions I've been have involved going bowling and putting a brick through a shop window. It seems a bit lame at the moment. The driving around is cool, but the missions are a bit so so. Does it get better??

Missions get more 'GTA' like when you get to the next island(s). The first island is pretty much a bit tutorial; "how to fight", "how to play mini games", "how to throw", etc. I thought it was a good change of pace though having missions like that. But don't worry it does get better!

Took me 29 hours to finish the story, 60 hours to get 100%. Didn't really ever feel bored but I really like the game.

will it ever be released on psp?

I had the exact same thought, mind you I've only put about 5 hours into it so far, glad to hear it gets better on the next island!

Doubt it as the hardware won't be able to cope. Rockstar wanted to do a lot more with GTA 3 but the limitations of the PS2 prevented it and that will be the issue with trying to port GTA iv onto the PSP.