Matt Cutts has recently release
this video of him answering a question about PageRank and why
it is still being used, even though its use has become less and
less relevant in recent times.
What is PageRank?
PageRank is a system which is used by Google to determine the
importance of a website using this formula.
As SEO's we previously placed significant importance on this,
correlating site rankings with higher the PageRank number. From a
metrics standpoint it doesn't really make a difference anymore but
it does however contribute to your websites indexing frequency and
also as a penalty indicator.
If your site has a higher PageRank Google will see this site as
being more important and will be deemed worthy of more frequent
crawling and will increase indexing. This means that when you add
(rich and engaging) content to your site it will rank quicker on
Google have just carried out a PageRank refresh and Matt states
that they will continue to do so as long as they see people are
seeing it in their tool bars but concedes that the "writing is on
the wall" in the long term. This is due to people upgrading to
newer browsers, such as IE 10, which don't support the toolbar
add-on, meaning this would see the PageRank toolbar be phased out
over a period of time as less people were using it