We used the one at the MK ticketing center last year for two nights. It worked well for us. You had to go at least twice a day to visit your pet and walk them. We had no problem with the condition of the kennel.
As someone said, the kennels have been taken over by a kennel service now. They will actually feed them and walk them now I believe, and the cost is a little more than when we were there. You can visit their website (I'm sure it's linked somewhere on DIS Boards) and see what is offered and the prices. Outside of the one review above, seems like this has been discussed on DIS and there were at least a few positive remarks about the service. I can't imagine Disney tolerating poor conditions which would reflect back on Disney.
Not sure what we will do this year when we go. We could board him with our Vet at home, but being gone for 10 days may stress him out. He is okay when we leave him over a weekend (though very happy to see us when we resturn) but not sure how he would take being there that long without us visiting him. At least at Disney kennels we would see him often and ease his worries about being abandoned.