Hi, my site was ranking inside the top10 for some long tail keywords, and top100 for some not that long but high competitive keywords. I did a few things and I'm trying to know what of those things made it happen. The site is an ecommerce site, with not too much text, but many pictures. It was ranking in similar positions, always getting better, slowly, but better, since the last 3 or 4 months. About the site itself, I didn't change anything. But the main change I did was to add a blog, in a "/news" folder, and I've been updating it with some new content and also some copied content (if copied with reference and link to the source). The blog has information and news about the niche, but in order to have information, the long tail keywords aren't always the same. Then, with the blog I added a sitemap, but I don't have a sitemap for the main site, and the webmaster tools understand a site in a folder as part of the main site, not a different site, so it understand the sitemap for all the site, not only for the blog. I guess the problem is related with the blog, but I don't know exactly what point. If the new links that I'm getting to the blog, if the content of the blog itself, maybe that sitemap is hurting me too much, or maybe I should move the blog to a subdomain to make it look as a different site .... I've been thinking some steps to solve it (sitemap for the main site with higher priority, more inlinks from the blog and finally maybe move it to a subdomain), but I hope to know your opinion about what did hurt the most, I mean, what was my mistake. To learn from it and don't repeat it. Thanks.
I doubt you made any mistake at all. I think a drop in rankings is more likely to be competition, a devaluing of current links or the removal of benefits gained through a "news boost". If you gave us your URL and the keywords you are having problems with, we might be able to suggest some more specific advice.