Wait, how can I tell you that pagerank doesn’t matter? Wasn’t I just talking about the importance of getting links from high-ranking sites? Didn’t I say that pagerank is a measure of how important your site is?
The above is all true. You do need to get links from high-ranking sites, and Google does use PR as a measure of usefulness. What it doesn’t tell you, however, is how relevant the page is. Let me explain.
Suppose you do a search for “how to shampoo the dog”. What would be more useful to you: a PR0 site with detailed dog-washing instructions, or a PR6 site selling dog shampoo? Obviously the former is a lot more useful to you, because it’s relevant to your query.
Similarly, while high pagerank is nice to have, your users don’t really care about it; they just want your site to give them what they need. Similarly, you just want your site to come up at the top of the SERPs (Search Engine Results Pages) so your customers can find you. Thus, you want to get links from high-ranking, relevant sites because they count as a strong vote that your page is useful.. provided they’re done right.
Next question: suppose you’re the owner of that webpage on how to shampoo a dog. Which would be more useful to you: a link from a PR2 page using the anchor text (that’s the words you click on) “how to shampoo your dog” or one from a PR6 page with the anchor text “click here”? Again, the former is more helpful; while the latter is better for increasing your pagerank, the anchor text only helps you to rank well for the term “click here” (which Adobe dominates), while the former tells Google what your site is about and helps them to return relevant results.
So do you care about getting a high PR on your sites? Well, yes – more pagerank is always preferable to less pagerank, and having a high-ranking site also speaks to the usability of new pages on that site that don’t yet have their own backlinks. Just remember: relevance trumps numbers!
In fact, Google has explicitly said that the PageRank system is one over more than 200 signals they use to index and rank pages. Remember, what they’re trying to do is find relevant, high-quality content; everything else is just a means to that end.