Nothing overly different, considering most of my time is spent playing older games anyways. Very rarely do new games amuse me much.
MW2 for example is criminally short and unreplayable compared to my favorite shooter of all time, Doom 2. Ruskies and terrorists < Demons and zombies.
Despite having beaten them to death, I still play a lot of Sonic 3 and Rome: Total War.
So in short, old games are better. In long, new games are too much about graphics and gimmicks like online multiplayer to be any good and people who care not about graphics will have generally have more fun with the older games which are designed for maximum fun and not tned to use more colors than brown, grey, black, and red.