It looks like Costco is trying to be competitive with their Verizon Samsung Galaxy Nexus promotion. They will be offering the device for $289.99. The deal is still a bit better than just a ten dollar difference though, because it also includes a Costco Member Bonus Accessory Pack, although the details of that have not been released yet.
This is all thanks to a pic tip, (shown above), although it is so blurry it is nearly unreadable. Interestingly, the pic still shows the December 9th launch date, although current rumors peg that release date as having been postponed by Verizon yet again.