I upgraded from the Treo 600 and let me tell you, this is a BIG upgrade.  If you have the 650, it may or may not be worth it, but if you don't yet have one of these devices or have a 600, I would give it a strong recommendation.

Negatives:

1.  I have installed the software on my laptop and desktop and have tried everything under the sun to successfully sync the device to no avail.  There are NO customer service numbers, only internet help sessions.  I have tried every single thing under the internet sessions and have still yet to successfully sync.  I am currently frustrated beyond belief because I love the phone, but I can't sync all of my previous data to it.  If any of you have any advice, please let me know!

2.  It's the same size as the 600 and 650.  It would have been nice to see a progression to a smaller device.

3.  The Windows interface is different than the Palm and if you are a Palm OS lover, this device is not for you.

Postives-

1.  I actually like the Windows interface slightly better.

2.  The ability to sync Word and Excel is huge.

3.  The almost broadband internet access is the real deal.  It's not quite that fast, but pretty darn fast for checking web based email on the go or looking something up real quick.

4.  The sound on of the person you are talking to is much better than the 600 and probably equivalent to the 650 from what I hear.

5.  The camera is a nice 1.3 megapixel and takes decent pictures, but has no flash or zoom.  The pictures are pretty good for a phone, however.

6.  The TODAY screen is nice and the ability to have your speed dials with their picture on that screen is a nice touch.

Overall, this phone would get a 4/5 if I were able to get it to sync easily.  The fact that I have probably spent 12 hours of effort is exhausting, disappointing and completely frustrating because I still have no solution in sight.  If, however, you are able to get accomplish this task with ease, have a 600 or are looking at this vs. the 650, I would say go for it.  The interface is user friendly, pleasant and refined.  This phone will do it all for you...and then some.
I upgraded from the Treo 600 and let me tell you, this is a BIG upgrade. If you have the 650, it may or may not be worth it, but if you don't yet have one of these devices or have a 600, I would give it a strong recommendation. Negatives:

1. I have installed the software on my laptop and desktop and have tried everything under the sun to successfully sync the device to no avail. There are NO customer service numbers, only internet help sessions. I have tried every single thing under the internet sessions and have still yet to successfully sync. I am currently frustrated beyond belief because I love the phone, but I can't sync all of my previous data to it. If any of you have any advice, please let me know! 2. It's the same size as the 600 and 650. It would have been nice to see a progression to a smaller device. 3. The Windows interface is different than the Palm and if you are a Palm OS lover, this device is not for you. Postives-

1. I actually like the Windows interface slightly better. 2. The ability to sync Word and Excel is huge. 3. The almost broadband internet access is the real deal. It's not quite that fast, but pretty darn fast for checking web based email on the go or looking something up real quick. 4. The sound on of the person you are talking to is much better than the 600 and probably equivalent to the 650 from what I hear. 5. The camera is a nice 1. 3 megapixel and takes decent pictures, but has no flash or zoom. The pictures are pretty good for a phone, however. 6. The TODAY screen is nice and the ability to have your speed dials with their picture on that screen is a nice touch. Overall, this phone would get a 4/5 if I were able to get it to sync easily. The fact that I have probably spent 12 hours of effort is exhausting, disappointing and completely frustrating because I still have no solution in sight. If, however, you are able to get accomplish this task with ease, have a 600 or are looking at this vs. the 650, I would say go for it. The interface is user friendly, pleasant and refined. This phone will do it all for you... and then some.