We were very lucky last week (Wednesday - Monday) in that we encountered few closures of rides that we wanted to ride at that moment. That being said, we saw Space, Buzz, Nemo, Star Tours, Big Thunder, and Toy Story all closed at least once. We went to get our Indy fastpasses mid-morning once when they were just bringing the system back up, so we had to wait briefly in line for them to do that; I assume the ride had been down. We looked at MouseWait before heading over to rides occasionally and were impressed by the number of closures listed sometimes during the day, but we didn't verify these all ourselves. My guess about all the closures is that it could just be the wear and tear of running these rides 16 hours a day, day after day. I still remember our New Year's trip of several years ago. I think we'd pretty much seen everything break down at some point or another during that trip. The boys refused to ride Peter Pan because it had broken down so many times they were convinced they would be stuck on it. Most CMs at the time commented that they felt like a lot of rides were due for maintenance since they'd been going non-stop for the entire holiday season and that they'd seen this pattern before.