The Tamagotchi Color isn't really the v7, because the Keitai and Keitai Akai Tamagotchi's were released in Japan only and aren't called the v3 or v4, there are completely different Tamagotchi's released here that are the v3 and v4 Tamagotchi's. If it eventually released in Japan then it will most likely be called the v7. At least, this is whaat I have come to understand through the
TamaTalk board and various threads.
Another reason that I do not think that the T+C is the version 7 is because there is a version 6.5, the v6.5, the Music Star Tamagotchi World Tour, which will be coming out this fall in america.