We haven’t seen this with my iPhone 3G and the 2.2.1 firmware, but apparently some users lost wi-fi connectivity after applying that firmware update. The problem seems to affect iPhones and older iPhone 3Gs, and it seems to be heat-related, as some users say putting the affected iPhone into the freezer for a short time temporarily restores connectivity. The obvious assumption is overheating, and some believe that what happened was Apple was throttling the wi-fi chip until 2.2.1 and that after removing that “brake,”