I'm currently doing the velocity diet. I am about 2 weeks in and am very pleased with the results. I started at 160 and am now at 154, and have significantly improved definition in arms and torso.
I've modified it since my willpower is not as strong as many of the others on the fitness forums. I'm doing the shakes during the day for breakfast and lunch, then the solid meal for dinner. I also skip shakes if I'm not hungry. Heres a link. It's not cheap, but its easy to buy everything from one place, and it replaces 2 meals a day for over a month.