Perhaps this isn't that surprising, given the relatively large installed bases and libraries the older systems enjoy over their current-gen brethren. What's more surprising, though, is the 17.1 percent of console time spent on "other" consoles that pre-date the PS2. What's causing this relative popularity of retro gaming ? Are frat house's still having nightly Goldeneye tournaments? Are speed-running Super Mario Bros. players more prevalent than we thought? Do today's kids enjoy marathon sessions of Parappa the Rapper? Without more detailed data, it's impossible to know, but it sure is fun to guess, isn't it?
PDF - Nielsen's 2007 Top Ten Lists