Well this weekend was/is Memorial Day weekend here in the U.S. of A.
Memorial day weekend in the past has set the trend for the summer here at Universal Orlando.
The wait times for the Simpsons Ride never went below 90 minutes the entire afternoon and hiked all the way up to 150 minutes.
My suggestion to those visiting the park during the summer is to get in early. If you get in at the time the park opens, you have the best chance to get on the ride quick and without much pain of waiting in line. Wait times at most parks are usually the shortest right at the start of the day, so remember go in early to what you do want to ride quick.
Those that are staying in one of the On-Site hotels, you are in luck. With your room keys, you get express all day at both theme parks. The room key can be enjoyed as an express pass at the attractions that have an "Express" line.