Pros: Lots of third party applications, better audio and great memory space.
Cons: Battery life could be better. Cheap frontal face material which cracks with no abuse

As a 650 user I decided to make the change. The 650 had many issues, like constant rebooting and all the other complaints many users had. Physically the 680 is very nice, ironically it is not as good as the 650 for one handed operation. My 680 has not rebooted once but it does have the tendency to temporarily freeze up while receiving or making a call. It is almost as if it had a sensor which gauges very important calls and freezes. Palm has improved the audio and the 680 does not need "Volume Care" like my 650. My 680 did develope cracks on the face which I thought was sturdy and solid but turned out to be really cheap material. Replacing this was expensive, over $100.00. I do believe that Palm designers are a bit arrogant and do not admit when they have made a mistake. Like the 650 they never admitted any thing was wrong so nothing to improve. All in all I would recommend the change to the 680.