Having good PR will help you sell more text links on your sites. You should worry not how high your PR is but how high your competitors' PR is so that you can beat them.
The pagerank for my first site updated almost 3 months ago. It was very exciting, even though it was low.
Actually PR relates directly to crawl frequency. Higher PR translates into more frequent crawling from the Googlebot.
Is that the PR of the home pages or the PR of the page your link is on? That would make a huge difference.
Hmmm.. Same PR update question again... 3 to 4 months... regular updates of PR. It will be on 2nd or 3rd week of August...