The PlayStation Vita is a nifty unit, no doubt about it. But there are some things it just can't do…yet.
According to Andriasang , players will not be able to access the Vita's web browser in the middle of playing a game.
In other words, when you press the PS button (as you might on the PS3 controller), you can bring up the menu and have access to several features. That includes your music collection, friends list, and the system's Twitter client, and you can always return to your game. But source Impress Watch wanted to clarify a particular point: you can't browse the web when pausing a game with the PS button. If you want to surf, you'll have to quit your adventure.
However, the good news is that based on the wording of the information, Sony might fix the issue with a future update. …we imagine a great deal of things will be addressed with updates and patches, which isn't a bad thing.