Count-down to 30

My boyfriend and I started the 3-2-1 Slimfast diet together on July 2, and we've been going strong for almost three weeks now.  We've each lost about 10 pounds so far through diet and exercise, and looking to keep going strong.  The big 3-0 is coming up for me in December, and I'd really like to start the next decade of my life in a healthier, fitter body.  I'm five foot, seven, weigh in at 206, and wear around a size 16 right now.  My goal for the end of the year is to be at or below 180, so right now it seems to be an attainable goal of losing six pounds per month.  My goal for 2011 is to get down to at least 160, but I'm really hoping to get down to about 140.