Back Link is still important

After the PageRank update on Sep 29, 2006, I found the backlink is still important. No matter what the kind of that backlink is, if it's not a bad link, it will benefit your site. I notice a website, which got tons of unrelated backlinks, PR changed from 1 to 5. Just like Google said:

When Google was a Stanford research project, it was nicknamed BackRub because the technology checks backlinks to determine a site's importance.

Google is still a backlink based search engine. So more backlinks and more cached pages, you will get higher PageRank. However, we also notice the Google's changes, but the content is still the king.