The gravitational pull of YouTube remains absolutely dominant and other portals - however clever their business model or technology - are struggling badly to make inroads.
(I would have added YouTube to the chart, but the other sites flatline on the baseline).
It goes to show, as ever with online businesses, the technology and functionality are nowhere near as important as the ability to gather critical mass. Marketing and distribution are all that count now.
The video search market is getting to be a crowded place, with names such as Blinkx, Ulinkx, Cast TV and Clipblast, but it's experiencing very little growth, only AOL's Truveo has seen any substantial growth over the past six months as the graph below shows: