Zeiss ZE, I've been testing them over the last few months and I am about to sell off all my L lenses and replace them with their Zeiss counterparts. I'll probably keep my 14L II, but if the Zeiss 15mm f/2.8 comes out next month I'll probably get rid of it as well. The focus ring/throw is infinitely better than trying to pull focus with Canon glass. It's incredibly sharp glass edge to edge and wide open, color rendition is beautiful, flare is incredibly well-controlled.
You could start with the 35mm f/2, it's a useful focal length and a nice example of what Zeiss lenses can do. The 50mm f/1.4 is $725 and also a great lens, but I prefer the 50mm f/2 Makro.
I've been shooting DSLR video for over 2 years now and have shot 70 bands in the last 7 months alone, so I've had quite a bit of experience dealing with L glass for video. As much as I love my L glass the Zeiss stuff is just superior for video, no contest for me. I never use AF so no sense in paying for it when the money could be going towards optical quality.