Wow, I didn't expect so many comments! I've been glancing back, but I haven't gotten a chance to respond until now, so here I go...
To those commenting that I'm too stiff (and morganshow11 saying I 'flop around') I have realized I was pretty stiff... part of it is me still adjusting to some of Magic's gaits... I haven't been riding her all that long, and only a handful of times in the arena. 2-Pak, who was the one I mostly before I got Magic, practically floats through all his gaits, and Ruby has a trot so jaunty it's impossible to ride through it smoothly... Magic is somewhere between, and I'm still sort of adjusting...

But I rode her the other day (just a short trail ride to check cattle) and I'm getting better. I keep wanting to sit straight up like I'm in a Western Pleasure show, though.
1dog2cats17rodents: On staying centered... also something I'm working on. It's a problem I've had for awhile, since I busted my hip, and I keep trying to compensate for how lopsided my hips are. Until I reviewed the video, I didn't realize how off-balanced I was. ^^;
Ponyz: That actually helped alot... it makes sense. I guess I never thought of approaching the barrel differently...
Masatisan: I'll keep that in mind. And I think it was shortly after we stopped filming, while we cooled down, I did shorten the stirrups a bit just for expirimental purposes. As for reining around the turn... I had a question. So I basically pull the inside rein down to near my knee, to tip in her nose... how about the outside rein?
Reining girl: So make it wider going in, and closer on the way out, if I understood that right?
Also, I had a few general questions.
For reins.... right now I'm using split reins (which probably contributed to my wiggly hands), but I'm planning on getting some new roping reins. I have a pair now, made of braided leather, but they're too short. Is there a particular length that roping reins should be, or is it just prefernce? And is there a particular material that is better than another? All I've ever used before for reins is my braided leather split reins, and I love them, but they're too long and hard to keep track of going around barrels.
Also, has anyone ever heard of a show requiring the horse to run to the right barrel first? A friend of mine who is in the same horse club mentioned that she thought most of our shows require that, but I can't get a hold of the woman running the shows until the end of the week. Thing is, when I first started practicing with Magic, I found out right away that she prefers the left barrel... she just seems to run better that way. For now, I'm not real concerned with winning first prize or anything, and I mostly show because it gives me an idea of how well she's doing versus other horses, so is it alright to just let her run to the left for now, or should I start getting her used to the right barrel right away?
Thanks for all the help, everyone~