So it takes time to get traction as with any serious software package.
So why do I mention all this? Its because a friend asked for some help on a demonstration he was doing in Unity and he had a little less than a week. The problem is, in about a week one can start thinking about getting something simple done in a system like this. A month would be more realistic.
And this is not an isolated situation. The fact is that there are dozens if not hundreds of these packages out there, each in their own niche, and none of them are terribly difficult to learn, at least up to a point. But it is not instantaneous and figuring out which ones to learn and become good at is not intuitively obvious, most of the time.
[10/16/2015 As an addendum, although it has taken longer than I like to learn elements of Unity, it is proceeding and it will be entertaining and useful to pursue this at least as far as doing a non-trivial trial application, maybe something in the so-called VR world which is certainly trendy right now]