Wheel Bearing Failure!

Hello Fellow Mazda Owners,
For the past month I have been hearing a humming noise coming from the rear of my 07 Mazda CX-9 GT. At first it was barely noticeable up until yesterday when I was returning home from work. The noise was so loud I feared I would not make it home.
Today I visited the local Mazda dealership needless to say after an hour at the local Mazda dealership the prognosis was wheel bearing failure on the rear driver's side so I braced myself for the repair charge. The price quoted for the repair was $612.00 part and labor with a 12,000 mile or 12 month warranty. Unfortunately, dealership did not stock the genuine Mazda part and I was force to leave my vehicle overnight.
After reading several post with prices charged I feel good with what I was charged. My vehicle is in mint shape with 80,000 miles. I feel I made out OK with charges on repairs. I’ll let you know how it rides when I get my baby back.

I agree that doesn't sound to bad if thats the only thing you have had to deal with in 80,000 miles. Is anyone else having wheel bearing issues?

Update!
I got my car back and the humming noise is gone!
Mazda’s dealership stressed the point that I needed a front and rear alignment as soon as I can arrange it.
I still get a low thumping sound coming from the rear, which they claim is from a bad tire wear. Mazda’s mechanic pointed out the tire (rear driver’s side-humm?) and I could see the uneven wear.
I plan to purchase a set of 4 tires and need advice.
I’ll align both front and rear when the new tires are mounted.
Thanks,
Ed

Alignment issue could also be linked to wheel bearing's pre-matured failure
and tire wear (of course).
One does not have to do alignment on schedule.
However, if you keep an eye on the tire wear, you should know when it is time.

Yours lasted longer than mine. I had similar sounds caused by a bearing failure at 35.5K miles. Dealer replaced both front wheel bearings under warranty. I have an MEPP warranty but it was nice to get this solved before the original Mazda warranty ran out. Dealer kept the car overnight because they didn't get to it the first day. Biggest problem was the truly awful Chevy Impala rental I had overnight. Overall the fix is fine but I wonder why a bearing would go so fast. The car has 36K miles now and is only 2 years old.

1) If it is a bolt on bearing, I'd just do it myself. 2) If it is a pressed bearing, I'd just replace the hub&bearing assembly myself (bearing will come pre-pressed). Either way is a bolt-on scenario + take it to a good tire shop for an alignment. Both scenarios would have to be much cheaper than a dealer, who will by the way only add more paint chips to your wheels with their impact guns.