Well...as with a lot of 680's, mine has the battery issue where the battery hardly lasts through the day. Even with minimal calling. Some report that their batteries began performing well after 2-3 weeks. Mine has not so I returned to my 8700g.
The Treo is still "fiddly", but less so. The size of the device really does allow for a lot of one handed operation. You don't "have" to use the stylus at all now, although it makes some ops easier.
Some negatives:
xxx8226; The Alarm still sucks. Have to reset every night..no options.
xxx8226; Device takes net settings from provider (T-Mob in my case) and won't let you change the default networkd connect method. So the fookin thing is always reset to T-Mobile Internet vs T-Zones and has to be changed after every resest
xxx8226; Speakerphone is weak on volume but plays very loud for tuneage. Odd.
xxx8226; Turning off system sounds turns off the email notification sound. Who the frack would do that? Weird
xxx8226; Itty bitty teeny weeniexxx8482; keyboard
xxx8226; Funky keystroke combos on IBTWxxx8482; KB to get special characters
xxx8226; Versamail still "fiddly" to setup. Have to do each account separately vs a master setting that you can then modify per acct if you wanted.
xxx8226; Headphone jack on bottom of device.. ugh.
xxx8226; Nothing like PocketDayxxx8482; (remarkable how I miss that app when I'm away from BB)
Some positives:
xxx8226; Takes 4GB SD cards and will use an 8GB, although not supported and won't show all 8GB until you use more than 4GB of the card..weird
xxx8226; Streaming audio and video (basic but there) out of the box
xxx8226; Syncs better with MissingSyncxxx8482; on my iMac than PocketMacxxx8482;
xxx8226; SMS and Email "name autofind" beats BB's implementation
xxx8226; EDGE as fast as my e61
xxx8226; Calendar is easier to use (for me! don't flame me..)
xxx8226; Import/Export .vcs and .vcf which weirdly BB STILL doesn't do (why not?)
All in all, it's not bad other than the battery life
I missed my 8700 while I was away and missed having all my email accts polled all the time. I couldn't do that on the 680 because of the battery...maybe when the Seidio batt's come out. I liked the calendar app the best, and really liked being able to export/import .vcs and .vcf from work to device so I didn't have to retype everything, or sync up just to get a few meetings or contacts.
For those who don't like Suretypexxx8482; on the 8100, this device might do them well. I can't see someone who likes BB OS with a full sized KB moving to the 680 from a 8xxx or 7xxx series device.
Anyway, that's my experience with the thing for two weeks. YMMV
Cheers.