Looks like they laid off state workers and now can't keep up with the registration renewals. You could go to Springfield, IL and wait in line but that's rediculous and who wants to do that?
Just make sure if you go to Springfield you have all of the documents you need so you don't waste a trip. It was an awful experience in that building 4 years ago, I'm sure its only gotten worse since.
I used to have to go to Lansing to do mine, which was a full day to get through all the paperwork, so ...