Geforce 8800GT will launch on the 29th and Nvidia will prove that it can ship the cards back to many etailers and retailers at the launch date. Do not be surprised if the 8800GT gets sold out soon after the launch, as this is going to be a very sexy product and many will want to buy one.
Some people might hold their breaths to see the Radeon HD 2950XT in action, as it will cost roughly the same and it will launch about two weeks later, but Nvidia is walking on very solid ground with 8800 GT. This single slot card looks attractive and it should be quite fast, as well.
We can confirm that the partners are making their own cards and that, at the same time, Nvidia is making reference cards for the ones who don't like to mess with Nvidia reference design. The boxes are being printed and the cards will be available at launch, on the 29th.