I am a Universal employee at one of the busier attractions and just thought I'd respond to you and offer some insight on what you can expect. The hotel access has just recently changed with the creation of the express program. It used to be that you would be granted immediate back-door access with the presentation of your room key. The new policy is that you present your room key to the greeter of each attraction and you are granted access into the express line. These lines are usually (and I stress USUALLY) limited to 15 minutes or less. The difference between resort guests and regular ticket holders is that you will not be limited to the number of attractions at which you will be granted express access.
I'm thinking that they're not explaining this particularly well to resort guests yet, because we have had a number of issues with guests expecting one form of access and getting another. However, when coming to the park on a weekend like Memorial Day, you will find the express access to be an incredible improvement over waiting in the regular line.
Just a couple of warnings though for the busier times. Express WILL be quicker than the regular entrance, but it gets busier as the park gets busier. Although they limit the number of passes that they distribute for each time period, the fact that there are now two hotels booked solid can lead to a slightly backed up express line at certain times of the day. For the more popular rides, try to go either early in the morning or late in the afternoon. Try not to go right after a show gets out (keep an eye on that show schedule) because people all flock like sheep to one or two attractions when they're let out.
Hope i answered some of your questions and sorry if I was too long-winded!
