Is Google Page Rank Really Relevant?

[VodaBot]

I was just wondering that Google might have designed the page rank system based on the premise that higher the links a site has from other sites, higher would be the traffic to that site. However, I see so many sites that are having a very high page rank (since they might be having links from so many other sites) but do not have a very good volume of traffic. Also doesn't this system undermine the importance of good and relevant content on your site? Again I have seen so many sites which do not have a very good content and also might be having wrong grammar in their content, but still those are ranked by google. Please share your thoughts on this.