@MaggieC
I was worried about this too and had already sent my letter as SDSU was the first school to accept me. However, I called them to ask if it was a "permanent" decision
because asking someone to make a decision about the next major step of their lives in 10 days is ridiculous! The girl I spoke to, Angela Albert, said that once those letters
are received, SDSU will send an OFFICIAL admission letter with a $250 deposit sometime late March/April. THAT will be the official permanent deal for them!
As is with most schools in CA, nothing is official without payment. -__-