I'm looking for a *free* source of current, reliable industry statistics related to the estimated % of websites making use of SEO techniques.
For example, I'd like to track down research findings about the % of sites found in page one SERPs that have some level of SEO methodology applied. Another example would be the estimated % of business-related sites that have had SEO techniques applied. And, that kind of thing.
I'm *not* looking for stats for on-page or analytics, nor on the search engines themselves.
I've read through many pages of WebmasterWorld posts...and checked links for those posts. I've been to DMA, SEMPO, Jupiter Research, and Forrester Research. DMA has some stats, but not what I'm looking for. Any potentially current, relevant SEMPO info is for members. The last two offer expensive reports.