- The ability to open multiple instances of Remote Desktop without resorting to a hack (though I do believe that each connection spawns a new instance of the app itself).
- Redesigned UI
- Support for Network Level Authentication (which makes connections more secure)
Microsoft Remote Desktop Connection 2 is free, and a Universal app. And as always, I would be remiss if I didn't mention the very capable CoRD, which is an open source replacement for Microsoft's tool.