So I've been playing around with 2.2 today and found an easy method to enable StreetView in any iPod Touch without any "No Carrier" messages, PLIST/XML modifying, or having to manually run any commands via SSH. All you need to do is to install StreetViewEnabler package from Cydia. Next time you run Maps.app you'll see the orange StreetView button next to the callout text of every dropped pin (whether it is manually dropped or displayed by a search result). I'm not sure if there's any other method to display streetview, but if there's one, it should work too. Enjoy.