I stopped at Best Buy on the way home to get a closer look. They only had the 880 and 659. 880 was only in a box, so I couldn't take a good look. I did get to hold the 659 and determined I didn't like play, stop, etc at the bottom. However, the 659 has hard buttons, which were just fine, so that rules out that as any type of deciding factor for the 676 vs. 680.

Taking a closer look at the two, it appears there are the following differences:

676 has: A, B, Guide, Info

680 has: <- (back), Live, Recd, i (more)

Info=I perhaps, so maybe 3 differences, other then placement of buttons of course.

Can anyone shed some light on functional differences here and what I am missing/gaining between the two?