At CES, Atheros and Broadcom showed working products based on early 802.11n chips: The demonstrations were off the show floor in private suites. These chips--along with Marvell, which had a chip to show but no working product--use the Enhanced Wireless Consortium (EWC) proposal as the basis of the silicon. Update: Metalink wrote in to note that they, too, were demonstrating EWC-compliant products.
Atheros, Broadcom, Intel, and Marvell formed this private, originally secret group to cut through a roadblock in the 802.11n task group, which has a goal of higher throughput for future Wi-Fi standards. The EWC was criticized for working outside the IEEE process, but their proposal now has dozens of members of the 802.11n task group signed on.
Marvell's chip isn't in sampling yet--meaning it's not available for manufacturers to start building products around--but a representative at the booth said it would be out any day. I was not invited to Atheros and Broadcom's demonstrations--if I had been, I would have been under non-disclosure, too--but I expect they are in a close to similar state. The companies could produce the chips in quantities in a few months, meaning that 802.11n-like consumer products could be out as early as May or June. Metalink is sampling now and expects products based on its chips in July.
The sense I got from being on the floor at CES and talking to a number of Wi-Fi equipment makes is that the EWC proposal will easily capture the majority necessary to move to a vote to accept a draft, and that it then has the 75-percent supermajority votes, too. Airgo is the only major wireless data chipmaker that hasn't signed on to the EWC.
I'm never quite sure how the IEEE establishes rounds of votes, but if both the votes are held next week, the EWC version will win the day and move forward. The IEEE's Web site puts finalization as early 2007 based on certain assumption.