I stayed away from X360 until the Halo Reach edition and then quickly went through the backlog of attractive exclusives like Halo 3, Halo ODST, Halo Wars, Gears of War 1-3, and couple of others. I dislike that I have been paying for XBox Live Gold Family when I haven't used it since Skyrim. Will probably use it again soon for Dawnguard expansion and then again for Halo 4.
My Wii was sent in to Nintendo for repair and they sent back a refurbished replacement with new System Code. I lost all my Nintendo Channel stats, friend list, etc. Proved to me that Nintendo System Code nonsense is retarded. I played Wii much less since I got the replacement. It was such a huge pain to friend list originally that I have yet to bother doing that again with the replacement console. Also, after Mario Kart Wii, there hasn't really been any reason to do any online anything on the Wii anyway.
My original PS3 60 GB that was BC fried itself eventually. I never sent it in for repair and just bought a new one (80 GB model that looks like original but no BC) and swapped the hard drive. Lost only time and money... but no data.
Bottom line... have not lost any X360, but have lost a Wii (frustrating with data loss) and a PS3 (expensive but no data loss)