I noticed a slight increase in my adsense earning after the page rank update, and wondering, if page rank might have anything to do with per click value? Or perhaps it's coincidence?
Sure. Page rank has a big influence on your adsense earnings. If you get a high pagerank, than you rank higher in the search results, and get more clicks and visitors, and you get more money from adsense. Thats simple.
I think PR doesn't influence on adsense earning. I have an experiance with this. I get $3.23/click from my new blog. You can read my post http://forums.digitalpoint.com/showthread.php?t=1360346 Only one of my blog have 2 PR and the other doesnt have PR (new blog). I think the best factor you will get big earning are your keyword, and the source of your traffic (better you get organic traffic). Just remind you, my blog is about student loan consolidation, auto insurance, debt consolidation, credit card, and health insurance
I think only keywords really matter. If you have good paying keywords in your content. You make more money. If you have higher page rank you might get more search engine traffic. Ultimately I think the following niche related things will pay more: Medical,Insurance,Travel,Law etc...
Even I don't think there is any relation between PR and Adsense. Its just the keywords that pay you more. - Digital -
I think its just that if your pagerank is increasing then so are your serps, so better serps = better earning...