Seriously, when Riv first started casting I honestly couldn't stand it, he wasn't very good and was easily overshadowed by Phreak, Deman and the rest of the more experienced casters. It didn't feel like he knew what he was talking about and he just let the other casters do most of the work.
Fast forward to the LCS last weekend and it's really crazy how far Riv has come as a caster. He obviously studied the game a lot and clearly knows what he is talking about, he is confident, he works well with the other casters and plays off of them, he has a badass beard and he has a perfect shoutcaster voice. He is easily on par with the other casters and I actually prefer him over some of the more experienced casters (won't name names).
So ya, Rivington the 3rd, wherever you are, kudos to your for your hard work and dedication, you've come a long way and are an awesome caster.
tl;dr Rivington goes ham in the paint.