Learning PHP is normally not requested when doing seo. But if you really want to bring your professionality to the cutting edge, I think that you...
Updating the content of your site won't hurt at all but it won't help so much your rankings: you need to build backlinks.
I suggest you to create a sitemap for your sites. If you link internally a website that has 4/10 pages you do not need it, but you need it for...
yourdomain/forum is better also for readability reason: it can be better memorized. http://www.seo-guru.net
if you increase the number of posts it won't help to show up in the first page. You need more links. http://www.seo-guru.net
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