I’ve had my MacBook Pro over three years now. If memory serves, I ordered it near 29 July 2007. And I’m quite happy that it’s still one of the fastest machines in the company and serves my needs quite well. I do wish it would support more than 3GB of RAM, but that’s not too big a deal.
It’s on its third battery (they fail after about a year for me) and its third hard drive (no failures, just upgrades).