Some nice things
I just got mine a couple of weeks ago. While you did ask about known issues, I guess it's only fair to mentions some positives as well.
1. The 4g, at least in my area (around Baltimore), is pretty great.
2. Patching the mobile hotspot is fairly easy, (if you don't mind spending a couple of bucks on the right app) which is quite useful if you're grandfathered with unlimited data.
3. The lapdock can be quite useful - emphasis on "can" - as you can have a full blown linux OS running on it (takes some nerdiness to get it working nice, but I honestly think it's well worth it since I paid only about $70 for my lapdock).
4. Rooting the phone is extremely easy.
5. If you mess anything up, restoring it to its original state is fairly easy and mostly fool proof (as with all motorola android phones) using RSD Lite.