I'm curious to know who has lost the most weight since using Jillian's plan and in what sort of time frame.

Who lost the most? It's not a race thank god because everyone is so different. I started Jillian's workouts back in the late fall I guess and I lost around 60 lbs. this past year but I haven't really kept records about when I was doing what. I have been exercising - and dieting - for years. Finally dropping my calories a little more and staying consistent about everything is what finally made the difference for me.

I went from 178 to 163...since last October...holy **** has it been that long? But more significant is that I went from a flabby size 14/16 to a fairly toned 10/12....I have been quite disciplined about working out - much less so when it comes to food intake.

I started Jillians program on March 22nd (yes, i remember the date exactly!) and i'm down 40.9 pounds (18 kilos). And i agree with ledom, it's not a race and we all have times where we may not be as disciplined as we should have been. Sure, i would have liked to have lost more, but i'm very happy with my progress and the results. It all just takes time, i didn't put on the weight overnight, so i can't expect it to come off overnight.
My diet's pretty good all of the time and i get in nearly all of my workouts, i just sometimes have a few weeks were i do everything right and i may not lose, but that's ok, i know the weight will come off, and i've finally found a program that works for me.