Well, the trackpad stopped responding - the pointer would dodge all over the place, and since I had "tap to click" set, things would randomly launch, close, etc.
I ordered the replacement trackpad from eBay, the tools I didn't already have from iFixit (BTW -this is the best spudger ever). Took about 90 minutes start to finish. It wasn't the most difficult teardown I've had to do on a Mac device, though, some of the components were the smallest I've ever dealt with.
Make sure you have all the right tools ahead of time. Also, some compressed air for cleaning out the computer would be advisable. Since you need to take the fans out anyway, it's easy to get in there and clean it out. I honestly think my computer is running cooler now because of it.
Also, be patient. NOTHING in this repair requires force to remove or put back together. If something seems difficult, re-read the directions, or take a break for a minute. The first time through I missed the latch on the keyboard ribbon cable, and couldn't figure out how to remove it. Once I found it, it was easy.