As the mother of a child with autism, I just want to say that it isn't a bad thing. It just identifies some special qualities that my son has and helps us to help him process the various stimuli that he encounters. So if you haven't had your son assessed yet, I would just ask that you not put any negative connotation on the word "autism" in case someone who evaluates him mentions the word. The word encompasses a broad spectrum of behaviors.
That being said, if you feel you are waiting too long on the waiting list, call other places and try to find someone who can check your son out as soon as possible. Have you gone through your school district yet? You may also try Hennepin County social services. Your son is too old for the 348-tots program but I'm sure they have other programs for older children. With all developmental issues, the earlier you can get the child diagnosed and into a program that addresses the diagnosis, the better your child will do.
I still regret that we waited until my son was over 3 before we started getting on waiting lists for evaluations. He was 4 before he received an actual clinical diagnosis. He now received programming and the progress he's made in a year is amazing. I just wonder how far he'd be right now if I had gotten him evaluated earlier.
Good luck.