If you're interested in D&D I think this interview has a lot of interesting tidbits in it: discussions about what they changed and why.
AM: What is the audience for today's Dungeons and Dragons, and how is that different from the audience for my Dungeons and Dragons, growing up in the '80s and early '90s?
AC: One thing we certainly saw over the course of 2nd edition was the audience did tend to age along with the game. The game was a very playable, a very entertaining system, but it didn't necessarily speak to the people who were coming up into the optimal RPG age category through new ways. When we were all playing 1st and 2nd Edition, we didn't cut our teeth on MMOs or console gaming or Facebook or any of those things. At best, maybe we had experience playing Monopoly or games like that, Risk, so that D&D was a totally foreign thing. That's just not true anymore.