I don't really agree, I think think that a system is a success if it does what the company intended it to do. The PS2 was a success, and the PS3 so far is a failure because they both were made to be market leaders which is clear by their loss taking strategies. If the PS3 sells 30 million it's a failure, but for gamecube to sell 30 million (it didn't even get that high) it would be decent.
currently playing: Skyward Sword, Mario Sunshine, Xenoblade Chronicles X