normally i would say don't bother buying in advance, it probably wont sell out. BUT...people on the list have been saying that their city's shows have sold out, and since you're coming from MI, that'd suck if you drove all that way and couldn't get in. so i'd say buy the tickets now.
kevin
ps - the house of blues is an awesome venue. i just have to type this on every post that deals with a show there haha...the sound quality there is the best i've heard anywhere in chicago.