Yeah, the sport has grown so much in such a short amount of time. It's truly amazing, and I'm very grateful for the hard work and money that the Fertittas put into the sport, because without it the sport would still be nothing today. Most people would probably still be calling it "human cockfighting" if it weren't for the Fertittas.
As for the Silva/Weidman rematch, it's a tough one to call. Weidman almost caught Anderson in a kneebar in their first fight, so that just gives you an idea of how dangerous Weidman can be when he does get the fight to the ground, which seems inevitable, at least at one point or another during the fight.
If Anderson isn't clowning around like the last fight Weidman won't be able to KO him on the feet, so it will depend on him taking Anderson down and either finishing him with a sub or TKO, or just being able to stay on top of him and do what Chael Sonnen did in his first fight against Anderson.
I could see either guy winning it, but if I had to bet money I think the safer bet would be Chris Weidman. He's got everything it takes to beat Anderson, he just has to fight correctly and follow a specific gameplan and he should have it in the bag.