BBC is no longer sharing it’s page rank because any external links are blocked.

For instance instead of linking to www.ecommy.com they are applying this crap:
http://www.bbc.co.uk/go/redirect.shtml?http://www.ecommy.com/

Read the full article here

Update: BBC wanted to measure how much traffic they were sending to other sites so that they could figure out how to send more.