I just don't know why you seem to think that states have the ability to declare bankruptcy, because they don't AFAIK. California will either need to make some very difficult decisions (cut spending and/or increase taxes) or turn to the feds for assistance.
I agree though that they need to make difficult spending cuts to ensure that they don't end up in the same situation during the next downturn. Either that or raise taxes to pay for all the spending (that's one of my big pet peeves, people want all these government programs but don't want to pay for them, they don't realize the money has to come from somewhere). Unfortunately this is easier said than done, spending cuts and tax increases are both pretty unpopular ideas.