Things are going to get very interesting re: Astarion when we reach Baldur's Gate. All the people who know him, but not about his vampire status, will be surprised to see him walking around during the day. Those who do know he's a vampire will be surprised and confused. Cazador is going to be surprised, confused, intrigued and possibly a little fearful - if Astarion can walk in sunlight, what else can he do now? And just how powerful are these new friends he's made? Should be lots of fun.
The two obvious outcomes of confronting his master are Astarion drinking his blood and becoming a true vampire (who might then be able to turn us) or just killing him and remaining a vampire spawn. As I said, I'm on board with the un-undead route, but I think it'll have to wait for the very end of the game if it happens at all.
