@SheldonS: I was writing games in C# with XNA so Unity was the likely choice. There were a lot of things about Unity that I didn't like: the interface, MonoDevelop v. Visual Studio, and stuff I purchased on the Asset store wasn't always the most straight forward to implement. I was about a month in when UE4 came out and after watching the workflow between C++ and Blueprints I was immediately sold. It all depends on which is more comfortable for you but I recommend trying out each for a solid month or two.
I disagree with Zion about Unreal's steep learning curve: you can make a game entirely in Blueprints and there are a lot of tutorials and samples to get you started. It took me just a few days in Unreal to surpass my skills in XNA and Unity... not only that the Blueprint system is actually teaching me to be a better programmer.