Lets say you have a page with five links, each pointing to a page. That page of links has a pagerank of 1. (using the tbpr scale for simplicity here) As we know so far, Google will credit 1/5 of that 1 point of pr to each linked page. Simply put, Google doesn't give pass more or less pagerank if there is more than one link to a URL.

Now, lets say you edit this page, adding a second link to one of the pages you already linked to. Now you have six links to five URLs. For pagerank purposes, Google ignores (or more likely merges) the two links to the same URL and still credits each linked page with 1/5 of this page's 1 point.

As far as how keywords and text are handled, there are two possibilities. Google may only consider the first link, and discount the second. Personally, I don't think that is likely, but I don't have any way to be sure. I think, though, it is more likely that Google considers the context of every link to the destination URL, but weighs them less.

Imagine that the target page is about dogs and cats. The first link on the links page has the link text "dog", and that is the only link from the links page to the target. Google will consider that a 1/5 of 1 point vote that the target page is related to "dog". Now, lets say that you add the extra link, this time with the link text "cat". Some theorize that Google will only credit the target with the 1/5 of 1 point for the term "dog". I think that Google will split the difference, crediting the target with 1/10 of 1 point for "dog" and 1/10 of 1 point for "cat" - the target still gets 1/5 of 1 point of pagerank, but each individual keyword is worth less.

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