I went to Costco to pick up some shirts and the old greys are all but sold out. The did have a mountain of new colors! They don't have black in many sizes.
All I had was my crappy cameraphone, so the colors weren't accurately captured, but these pics will give you some ideas:
I'd say Slate is my new favorite since it goes with either khakis or jeans.
Slate
Purple (not for me, but it does look nice)
Light Blue
Dark Blue (more like a royal blue)
Green (seafoam green)
There's a few people I'll be IMing who were asking about different colors.