Very little between them. I use a Touch at home and in the car and it's brilliant. The bigger issue is storage capacity: the 120GB of the Classic can come in very handy, especially if you want to store lost of higher-quality Apple Lossless files. The Touch is a bit meagre at 8, 16 or 32GB.
There's a full review of the 32GB Touch in the Dec 08 issue of the mag, on sale now.