I would like to say that I don't see Unity as being the same kind of serious option as Unreal or the Cryengine, yet.

Their product sure is impressive and easy to set up and from what I've seen it is great for getting started and making smaller indie games.

However, it doesn't seem to have sufficient support for the kind of large collaborations and processes that you need when making a AAA game. I have read that they've done improvements on some of these things (making their data play nice with revision control systems, for instance). But I'm still not sure they are there yet.