I've had the V710 since it came out in August. It's a great phone, but you have to really mess around with it to get it to do what you want. The Bluetooth is crippled, but file transfers do work via Bluetooth with Motorola's MPT program on Windows. Only hitch is you have to do a
seem edit (hack) on the phone to get it to work. Also, you can get a transflash memory card that you can use to transfer pictures to your computer. You can also use MP3 ringtones from your computer, but again, you need to do a seem edit. Picture transfers work without any hacking.
The camera is horrible. Don't plan on taking any serious pictures. It's a 1.2 MP camera, but it has to be the worst quality camera I've seen anywhere, period. I use it regularly, but am always dissapointed with the photos. As for other features, I use the phone as an MP3 player. I've got a 128 MB transflash card (going to get a 512 MB card in a month or so) which I fill up with tunes. I use a normal pair of Sony Earbud headphones, and the sound is in stereo (you just need a cheap adaptor to use normal headphones). You can also watch movies and TV shows on it (MP4 format). I've actually put a full length DVD on it. While it's not really practical, it was cool to do.
The internal screen is gorgeous. Large active matrix transfective. Readable in daylight. The external screen is a reflective passive matrix screen, so it's super readable in daylight. It's also one of the largest external screens around, which makes it easy to use as a clock (big numbers).
The voice dial works really well. You don't need to train it, and it does digit dialing too. I've found it to be very reliable. Also, the speakerphone is loud and clear. Battery life is so-so. I find I need to recharge it everyday, but that doesn't bother me. The phone is a little large, but it fits well in my pocket. I think it's fairly attractive too.
Syncing works well too. On Windows, you can sync via cable or Bluetooth with the Motorola MPT software. USB cable syncing is the only supported means on OS X, but there's a hack you can do to iSync to make it sync over Bluetooth. I've gotten it to work, but contact syncing over BT with iSync isn't reliable. I also use the Bluetooth to go online with my PB on Verizon's 1xRTT high speed data network. It's about as fast as dialup, but it's great when you need to get online in a pinch.
As for games, you have to turn to hacking again. A few weeks,
java was hacked on the phone, so you can run Java games. It's a pain to get this stuff working though, and there's the risk you can damage your phone doing all these hacks. Many people have successfully gotten these things working though. I've reflashed and seem edited my phone many times. My point is, you can do pretty much anything with this phone, but it takes time and patience.
I don't know how well Cingular's service is, but I know Verizon's is excellent. I've been with them for three years and travelled all around the country. I've never been dissapointed with their service. In the end, I think it comes down to service. I believe you have two weeks or so with either carrier to test out the service before becoming committed to the contract, so be sure to take advantage of that.