The focus is kinda tricky on this projector and if you're focus is slightly off, then it affects the 3D performance.
I initially used the grids that displayed when manually focusing through the projector menus, which seemed absolutely fine but every time I watched something in 2D, the image looked slightly soft. And it would really be difficult for an average viewer to tell, but I work with blu-rays daily so I have a keen eye for picture detail.
Anyways, I skipped the girds and finally used an actual 2D image to focus on (e.g. I used the 2D Columbia logo from Cloudy with a Chance of Meatballs to set my focus). And when I set the focus on that, I noticed that in the focus menu, one button press (for focus) in either direction (from the correct focus position), the focus is off slightly; there is no leeway.
When I finally got my projector perfectly focused, I noticed there was a dramatic improvement in 3D: noticeably less crosstalk, the 3D depth looked better, brighter image, and also, strangely, the 3D image looked sharper than 2D. Before, I was a little disappointed b/c I was getting an unusual amount of crosstalk and the image looked too dim and I thought that was just how the projector was, but now that it's focused correctly, it looks amazing. And projecting at 119" vs. viewing 3D on a 50" plasma, is like night and day.