Well, mainly its just an updated version and 1st generation doesn't have built-in speakers like the 2nd does.
one generation
well the 2nd generation has built in speakers, youtube, access to email, and a bunch of other crap.
the second generation is thinner and has better software
4th generation is more updated and advanced
A lot slowerBack is differentDoes not support some appsNot as sexy
that the 4g is a bit thinner, have built-in microphone and cameras
A second generation iPod touch costs $200 if you buy it new
ipod touch 2nd generation
Well... the difference between the 1st generation iPod Touch and the 3rd generation iPod Touch is SLIGHTLY different. The cases will STILL WORK!!! (you are relieved :) ) The difference between the two generations is that the 3rd generation is slightly slimmer that the 1st. The thing is the cases made for the 1st generations might me a little big... (by a few centimeters!)
The second generation iPod Touch does not have a built-in microphone, but you can connect the new iPod earphones with the controls, which does have a microphone and will work with the second generation iPod Touch.
It's just white and a 64GB model
The 32gb has an additional 24gb of memory.