I try to remember to use a hard surface mat when cutting batting. The blade doesn't cut the mat so the batting doesn't get stuck in it. I bought Batting scissors. They are better then a rotary cutter for batting. I couldn't believe how easy it was to cut through batting even high loft with these scissors. Trimming a quilted top is like cutting through one layer of fabric. Some of my guild members thought they were just an expensive fancy item until they got to use mine and see for themselves how effortless it was to cut batting. There is even a video of them being used:
http://www.youtube.com/watch?v=xcdNxmpUboY