It does look like N. gracilis, I'll have to take a closer look when I get home.
The pitchers have been growing like crazy since I set up the tank, I guess it's just ideal conditions (always 18-25 degrees, 75-90% humidity). I've only fed them once, and that was just from a flightless fruitfly culture. I just happen to keep them better trimmed when I'm at home, heh.
Last semester when I was in school I supplied my entire botany lab class with pitchers to dissect, and I didn't even take half of them.