The next 2 versions of Unity are extremely interesting. It looks like they really try to enter the AAA market:

Unity Announcement

• Allegorithmic Substance integration (procedural textures)
• Better Shadows
• Multicore Rendering and Skinning (2-3x faster)
• Graphics optimizations, like improved deferred rendering
• Terrain works on mobile platforms also

But I am even more excited about the 3.5 features, especially directional lightmaps (radiosity normal maps), lightprobes for lighting dynamic objects, it will calculate paths from level geometry and there is a crowd simulation, better particles, visual GUI editor, better occlusion culling.

All in all it will allow me to use features that I know from UDK or Vision3d. If they implement it right, they will offer a really competitive technology. And the best: these announced features work on mobiles too, as you can see here:

http://blogs.unity3d.com/2011/06/08/advanced-shading-and-lighting-for-mobile/