Thanks. I agree with your post. Sales for CupcakeWrapperCreator have gone like this:
March 0.02
April 38.85
May 64.75
June 76.75
July 122.60
August 99.80
September 129.75
October 109.75
November 199.60
December 119.75
January 149.70
February 249.45
March 369.25
So, for nearly a year I didn't have any motivation to do more work, but then I signed up for a free month of SEOMOZ, and just fixed the low hanging fruit from their suggestions, and traffic doubled for last Feb.
So now it's a little more interesting. I can make $369 in a month with 150 uniques per day. What can I do with 300-500 uniques per day? And I think I can get there easy because just one blog comment I made is responsible for 20 uniques per day and I know I can outrank that blog page with a little work.