A certain social bookmarking website that i perhaps wish to use, utilizes a URL to themselves that results in a 301 permanent redirect to the websites that I bookmark. (example ... http://example.com/redirect2u.php?site=bookmarkedsite.com, and that URL's header once loaded is actually a 301 permanent redirect to my site I bookmarked). Now, I know if you take a preexisting URL that has content on it that contains certain keywords etc. ... if it has many links pointing towards it, once that existing URL with content and incoming links gets 301 redirected towards a new page location, that new page location receives the benefit of those backlinks, especially if the content is similar to the page content from its original location. However, when this social bookmarking website performs their 301 direct, that URL never existed before, never had content on it before, they're just creating it on the fly and 301 redirecting off it to the sites I bookmark. So my question is this ... when a brand new URL that has never had content on it receives a backlink from my profile on this social bookmarking site, does google consider this 301 redirect as a true link to the new location? Specifically, I'm looking for someone who has used a social bookmarking website that 301 redirects a link to themselves to your bookmarked site, if you have found it beneficial for either gaining pagerank or for ranking better for the terms in your anchor text. No guesses please, looking for someone who has personally observed this one way or another with their own use of social bookmarking that operates like this.
I know for sure that Google follows the link - it shows such bookmarked 301s in webmaster tools as links to the pages they're pointing to. As far as building pagerank and SERPs, well, bookmarks are of limited effect but they do seem to help a bit. How much it makes a difference is up to the other factors involved like the PR and relevancy of the pages being linked from, number of OBL, etc...