Correcting an earlier misconception we reported: NBA 2K12 will offer codes for two classic teams, the 1990-91 Golden State Warriors and the 2001-2002 Sacramento Kings. These codes will be printed and inserted into all retail copies of the game, and will be available through all retail outlets, but there will be a limited supply of them. Once the codes run out, the game will ship copies without them.
Kotaku had erroneously reported this was a preorder bonus through a specific retailer. It is, of course, meant to give incentive to buy the game on the day of release or close to it. The exact number of codes to be distributed was not specified.
Including these two, there are 34 classic teams that are unlockable and playable in NBA 2K12; while there are 15 "Greatest Ever" matchups comprising 30 teams, two of them are additional Jordan-era Chicago Bulls teams that are unlocked for defeating the 1993 Charlotte Hornets with the 1993 Bulls. The extra Bulls teams were seen in last year's NBA 2K11.
You can contact Owen Good, the author of this post, at owen@kotaku.com. You can also find him on Twitter, Facebook, and lurking around our #tips page.