Owensmom -- as I've said many times, Sirius was my favorite too!!!
It is so sad to think that he's "gone." And, like you said, even if he comes back in spirit or whatever, he's no longer flesh and blood -- I hate that!!
Oddly enough, my 2nd favorite characters in the series are Fred and George. Back when mamapie started the "who's your secret HP crush" thread, I was going to post Fred & George (can't decide which one I like best, so I'll take them both), but I was too embarrassed! After all, they were still underage in Book 4, and I didn't want to be an old perv. (Now they're adults though, so it's ok!)
I love how they were written in Book 5, especially the scene when they left Hogwarts. I was on edge thinking that Filch was going to whip them. Ah, but then they flew away into the sunset and I cried for joy!! I can't wait to see what they do in book 6.
Oh yeah, I love the casting of them in the movies too. Perfect!
I've been frustrated with Harry since book one, that he doesn't open up with his friends or with Dumbledore. In every book there are things that I think he should really share with someone, but he just keeps it to himself. Maybe that comes from spending his early years with the Dursleys (with no one to talk to)....but it is frustrating sometimes!
I don't know what I think about Snape yet. Can't decide what he's up to exactly.
I also thought it was great that Ron is out from under Harry's shadow in Book 5. It's about time! And I found it interesting that Harry was a little jealous of him for a change. My ds is especially thrilled that Ron's the Gryffindor Keeper now. Ron has always been his favorite character.