There was a comment about the vizard form slowing him down once, though I'm not sure if that was permanent or just because he wasn't used to it.
Grimmjow and Byakuya are both supposed to be pretty damn agile. Byakuya due to Yoruichi training him (I wonder if he'll be another 2nd division officer in this flashback arc?) and Grimmjow due to being, well, a cat. And that privaron was definitely outsped, considering that Ichigo's initial strike after going bankai got him through the shoulder and shredded half of his release.
As for Ulquiorra, at least in his unreleased form Ichigo did seem to be faster (he didn't have time to react to Ichigo's first attack set). It's just that Ulquiorra is so much more durable it didn't matter.