The question is: who can sign him for more than the MLE. The LAL can sign him for whatever (bird rights) or sign and trade him. Otherwise, let's say he wants a bad economy version of Tay's deal that goes 5 years and runs from 7 to 11 per year over the course. What team had 7 million in cap room now and is willing to spend it on Ariza, rather than waiting a year? Ariza is talented, but he's playing next to Kobe and I think teams are a bit wiser (or stingier) than in past years because of the economy.
So let's guess his options are full MLE at club of his chosing, resign with LAL for a bit over the MLE, or have his agent work out a S&T with LAL and another club. I can see both LAL deals falling through, LAL will basically need a dance partner that can send back a viable championship piece and have cap room. But again who has cap room? As for resigning with LAL - let's say they find a way to dump Morrison and Famar, they still are heavy at the wings with Walton and Sasha playing with Kobe - and don't they need PG help more? (I doubt they trade Fischer b/c of loyalty and other teams not wanting him.)
Anyways - if all that's left for Ariza is the MLE or a slighly sweetend MLE type deal from LAL - I could see him bolting. Then the question is where does he go? Boston would mean coming off the bench, but Ray and PP aren't long for the NBA at this point, taking a max 3 year deal at the MLE, and hoping to cash in when Bird rights kick in could be a good plan. MAybe even get an option on the third year in case the FA market is better after the 2010 class passes through.
CLE - LBJ sits right in his way. ORL has a host of wing guys, but could actually still use him, and Turk could opt out. San Antonio would be a nice fit, he's not as much of a shooter, but he'd probably be their starting SF.
I think he definitely has options and the C's will be in a position that they can only offer him what others do, so intangibles come into play - does he really hate BOS? How much would being on a winner come into play? He'd have a chance to be the guy stopping LBJ next year, and rubbing it in on his former ORL and LAL teams, who knows.