Tonight was my first class wearing my pretty yellow belt. =-) Already they're treating me differently. For example, in my first kata, they're now making me focus more on doing it with "power"--instead of just going through the motions as I did when I was learning it, I have to do each move with power and strength. In other words, instead of just raising my hand in a block or extending my arm into a punch, I have to do it like I mean it. I don't know if I'm explaining it in any way that makes sense, but it basically means that I'm not getting away with certain things I did as a white belt.
The other thing that was cool is that I started learning my second kata (the one I'll be working on for the next 4 months as I train for my green belt). I've already picked up the (albeit small) section they taught me tonight. Before, when I was first learning my first kata, since I was new to karate, it took me a long time to master even the basic moves--but now, I'm able to catch on a bit more quickly.
All in all, I'm very excited right now.
PS--right now, throw a punch straight in front of you. Then freeze and look at your first. If you're like most people, your fist is vertical, with your knuckles on top. Now turn your first sideways into a "vertical fist," with your thumb on top. This is how we punch in Isshinryu. Throw a punch this way. Does it feel totally unnatural? Yeah. I know.