Wil Reynolds of SEER Interactive (A Philadelphia based SEO firm) gave a speech regarding common myths with SEO (search engine optimization). Take what he says with a grain of salt. I liked what he had to say about inner linking. I didn't like what he had to say about metatags. He was some good things and bad things in this video. The SEF URLS and mod rewrite part is very good.

Also that rule about PR on inner pages isnt so hard and fast. This page has more PR than the main page:
http://www.photo.net.au/photographer/