Business now have real skin in the game and will run scared. Until now, many businesses, large and small, have enjoyed the status quo. They get a low-cost labor pool, often subject to terrible abuses because the businesses know these workers have no recourse. Suddenly, it is either get serious about screening for illegals, which means paying minimum wage and obeying other laws around worker safety, or risk getting your business shut down. And while only 8 states have these laws so far, you can bet a whole bunch of other states will now adopt them.
What the business community would like is for Congress to just preempt the law and otherwise leave the status quo. But that is not going to happen politically. The members of Congress (primarily Dems at this point) who want something like the Dream Act are not going to support letting businesses off the hook so they can more easily exploit undocumented workers. Those opposing reform (primarily Rs at this point) cannot be seen as "soft" by preempting harsh state laws.
So the only way to get out of the trap is with some kind of actually comprehensive reform. I don't think that happens before the 2012 election, alas. But if Arizona and other states are serious about enforcement, then we will soon see Chamber of Commerce and other business interests lining up with others to push for "rational" immigration reform.