I do SEO for a living (full-time job) and have been doing web marketing for some 9 years now. Now having said this, if you ask 10 seo 'experts' on how to optimize a site you will get ten different ways of doing it. When I provide advice is based on my experience - search for 'sports supplies' in google and among the top five results you will find a company with a ssww url listed - that's my work.
Do not confuse PageRank with natural search listings. PageRank helps in the sense that your site is listed in another site and might send traffic your way. It also help, IF the other site has a PR of 5+ (important site in the eyes of Google) then Google will follow the links (if it is not a link farm) faster.
Some rules that have worked for me in getting sites ranked high in natural searches at Google, Yahoo, MSN, AOL, etc.
1. Title of your page
2. Description of the page (describes the content of the page and of course will have keywords from your title),
3. keywords that match the content of the page.
Now, many say that Google does not take into account keywords and I might agree with that - but consider it an exercise for the other SE that do take keywords into account.
The title and description of each one of your pages should match the content of the particulaer page - if you use the same title and/or description in all your pages it could be interpreted as you trying to "keyword spam" a crawler.
I run affiliates programs and it never ceases to amaze me how many people leave the "New Page" as the title of a page... or have the same title and description in all of the pages of their site, then wonder why they are not indexed!
Optimize your images - if you are showing a digital camera insert that in the 'alt. text" of the image - Yahoo loves that stuff.
Use anchor text in the content of your pages (anchor text is a link to another page - example, if you sell computers and describe this on your home page, then link the word computer to the section you have about computers).
Do not jump off the roof if your PR goes up or down - it happens, especially when Google does its 'dances' 3 or 4 times a year. One particular 'dance' happens on or about December 14 - 17 every time without failing.
Unfortunately we are not allowed to include our email or urls here - but if you follow the google search term above just send an email to glamadrid care of that company - I will get it and get back to you.
Hope this helps.