The main differences b/w old ipodtouch's firmware i.e 2.2.1 & 3.0 are:
1)Copy/paste function
2)YOUTUBE: now we can use the builtin youtube app to login......secondly,now we can view comments of vidz too
3)Bluetooth feature(for stereo headphones)...below is the pic:
4) Auto-rotate while typin(now we can type in landscape mode)
5)Now we have the search option in the homescreen(below pic is available) :
6) Voice recorder app known as
VOICE MEMOS
7) In settings tab there is a separate option for autofill.....it enables the iphone/ipodtouch to enter login information automatically
PS:
Soon i will post the review of 3.0 firmware on iphone too