Technology decreases, true. But media and software don't count, only hardware does. People who comlain about a PS3 being $400 today would be up in arms when the same tecnology (it it existed) would cost $100,000 in 1998. That's the only reason technology comes down, it's all about hardware advances. Media technology is not the same. Plus, like someone else said, there are teams and teams of people working on games. It costs much more to produce than in 1982. And even in 1982 you were paying $40 for Pitfall!, while it was worked on by just one guy. So games today are a bargan.
Comparing CD's are totally different. A CD in 1989 is the same as a CD in 2009. A game in 1989 however wass far, far less to make than in 2009.