doc_z - 8:10 pm on Feb 7, 2007 (gmt 0)

Also I need to ask you what about linking to other sites from home page, will that cause the PR to leak?

If these links are non-reciprocal then there is a leakage of PageRank, i.e. the inner pages as well as the homepage will decrease in PageRank. (However, the effect might be too small to see it on the toolbar.)

An example of the effect can be found here [pagerank.suchmaschinen-doktor.de] - compare example 6 with example 8.

The results can be very surprising and often the opposite of what one would expect. For example, additional outgoing links on a page can actually produce an increase in PR for that page.

Not in case of non-reciprocal links.

...seeing as PR is a product of incoming links only, nothing else effects PR.

Of course, PageRank is a sum of incoming links - however, these additional links affects the PageRank of the page with the incoming links.