My old film camera can sync at all shutter speeds! Hooray for leaf shutters. However, to the question at hand-
I say get the cheaper camera and get flashes that can do wireless TTL. I think it'll make more difference to how you shoot than 1/3rd stop of extra sync speed. The commenter on the strobist article that was talking about 1.3 stops was referring to 1/200 vs. 1/500 that was offered on some older Nikon cameras that used electronic shutters. I think Surfsama is spot on, although aren't SB600's discontinued? Also, I wouldn't rule out PocketWizards. You're saving $900 by going with a less expensive body, that should give you serious wiggle room with buying other toys.
Disclaimer: My DSLR's are Canon, so I never had this option of ultra-high sync speeds that the strobists love so much.