Having used both a Gen1 and Gen2, I would have to say that the difference aren't "minor". Major differences include
1) The fact the the USB drives turn off
2) They fixed a hardware issue which caused the remote to be extremely flakey with Samsung and Philips television sets (it's not very well documented but you can find info on the web about this)
3) Much much faster due to the fact that they used the same sigma chip that is in the Live
4) DTS stuff which has been mentioned
4) File manager, which could be included in the Gen1 but hasn't been
5) And yes, other minor differences
For anyone reading this post trying to decide between the two (assuming the Gen1 would save you money), I'd definitely pay around 20 to 30 dollars more for a Gen2 just because it's considerably more polished and more functional.