OMG so funny you posted this right now. A friend just bought a hobby shop so he's getting back in and dragging me with him. I pulled out my cards (about 25k of them from Alpha to just before 5th) and realized I was behind the times so I grabbed a 15k card collection (expansions from 5th on) on ebay to catch myself up. So far I'm not a big fan of the newer stuff. Some great cards out there, but the game lost its flavor and balance (IMO).
Now that the bug has got me I ordered a few sealed boxes so I can experience the giddyness of sealed deck tournaments again (ala revised, 4th, ice age, etc). I really think the turning point was around Ice Age when they started messing around with new abilities, etc. Nothing beats 4th and before for pure Magic excellence.