For Me:
MS - Xbox 720 in 2011 (6 Years after 360) - Better one is $400, cheaper one is $ 350
Sony - Playstation 4 in 2012 (6 Years after PS3) - Sony Learned there lesson this time around - 1 SKU and it starts at $400.
Nintendo - Super Wii (ie. NES -> SNES) (6 Years after Wii) - $300 cause it will be HD.