Another thing I did a couple of weeks ago was to increase the life of my domain name. Previously the .net was only purchased for one year, and now the I have secured the name for five years.
Two weeks later - after running a keyword trawl - I see I now have a lot better SERP positions, especially in Yahoo, but as there are so many factors in
SEO it's hard to pinpoint this as the sole cause.
There is a school of thought in
SEO that having a new domain name with only a one year lifecycle is a sign to SE's that your site is for spam, increasing it to a long length is a reassurance to them that you are in it for the long haul and not just after a quick buck. Who knows.