I read years ago (probably on Yahoo.com) that click through rate is a primary determinant in SERP (search engine results page) rankings. Still true? If so, what is a good click through rate to maintain a good SERP ranking?
SERP has always been a part of any SEO campaign. CTR is related to SERP, but it does not really affect ranking. I think it's more related to the number of impressions by keyphrase.
Can you elaborate on that? I can say from my experience that meta descriptions are at least important as a tool to get search engine users to click on your link. For instance, the meta description on one of my pages is "One home health agency doubled new patient referrals after 90 days. Learn how free." When Google displays that description to people who are searching for home health marketing strategies, people click the link.