It's unfortunate that you're not seeing any benefits and are getting even more frustrated, but I think you might benefit from reading Paleobird's calorie counting thread that she posted today http://www.marksdailyapple.com/forum/thread29501.html
From reading her post, I know that I'm plateau'd because I've been taking in too many of my calories from fat and not enough from protein.
It can be really confusing when you've got athletes, men, women, recovering anorexics, former vegans, etc. etc. all giving advice from different points of view ... and I think we're all giving you advice because we don't want you to quit, we know that PB will help you, you just have to figure out the right ratios.
I think you're probably still taking in too many calories for your current activity level (congrats on starting exercise BTW!) but if you up your protein percentage, I think you'll feel a lot fuller. Also, are you drinking enough? Thirst can masquerade as hunger. If you don't like to drink a lot of water, have a broth soup with your meal.