I suppose I think Maggette goes to the Spurs if Brand goes to Philly, but I am not quite sure why I think that.
I haven't seen any comments legitimately attributed to Maggette that indicate a preference for San Antonio over Boston (please point me to something more than speculation).
Logic creates no clear front-runner as far as I am concerned. San Antonio has better weather and a starting role. Boston has Maggette's former coach, a cohesive team of veterans coming off a championship season. Maggette has never played more than 36 minutes per game and will probably be right around 35 whether he plays for the Spurs or the C's. Don't the C's as constituted have a better chance in the East to get to the finals than the Spurs in the West?
If Maggette decides to choose among teams offering the MLE, I really don't see why San Antonio is the logical choice. If the C's really want him, the 'sales' team of Doc Rivers, Danny Ainge, Paul Pierce and Kevin Garnett has no equal. Inspired by Tim Duncan? Wooed by Manu Ginobli? Cajoled by Tony Parker? If money is no object I cannot see why San Antonio is a more likely choice than Boson.
That said, I am influenced by the power of consensus here and I think that if so many wise cbloggers think San Antonio, you must know something I don't.