Yeah, you definitely look a little slimmer there. Great job!
I'm ~170, near normal for my height of 6'1". In mid 2004 I was way underweight, as I was only 99 lbs at 5'7"! That was down from 130 the year before that (I think I was 5'4" in mid 2003) because I thought I was overweight at that time, though it really wasn't that bad.
Wow, I used to be like that. I was really underweight in elementary school. Then my weight shot up in middle school, and is now decreasing again. Currently I weigh about 130 lbs and I'm about 5'8".
High school will do that to you. As your body grows and shit, your body metabolizes faster. Be glad it does that now... as you get into your early 20's, the metabolism tends to slow back down and you can gain weight quickly if you're not careful. My metabolism's beginning to slow back down now that I'm 19 because I've gained 15 lbs in the past year, thus I'm no longer underweight for my height.
I used to weigh 130lbs at 5'11 throughout my late high school years, and I'm now at approx 145lbs at 5'11 today (I'm 19.30684931506849315068493150684932 years old atm)