I'm now worried this is opening a can of worms that I knew was on the horizon. My macbook pro is 4 years old. I love my old Illustrator 10 and my old (now not functioning PSE6) Uggh - I don't want to have to buy all new products!
I've just upgraded my "old" MacBook Pro (mid-2009, 15-inch) with 8GB RAM, $82, and 1TB internal drive, 7200 RPM, $98, and replaced one damaged key, $7. It is a lot peppier now. Feels like a new machine. Looking at a new batteriy... $120. for 72Wh.