Being able to delete stuff, create folders without interrupting the music you are listening to This was a major prob the Psp had, and not only that but it should also have uninterrupted experience while heading to the options such as thenes and other things.
They should work on bringing their current service internationally such as Qriocity and Digitals Comics Dude! doesn`t that annoy you when you want to get an eye at a service and find out it`s not available on your country?
Introduce the new Ps2 Classics before gamer ask so! Personally I think there are still a lot of ps1 games that should be on psn including Spiderman, Tony Hawk, theses Tomba games and more! but maybe it would be cool to start supporting both at the same time! :D
Add Steam integration so users can keep in touch with their Steam friends of "friends"! An app for that would be awesome! I've always been dreaming of it!