PR4 or The Google Gods Smile at Colnect

Some time ago, I've posted about Colnect's rank of PR0. Yesterday Colnect still had the embarrassing PR0 but as of today, Colnect got it's PageRank updated to 4!

So this is good news but some questions are left pending:
* What was the initial reason for PR0? What was my sin?
* What has now changed that Colnect deserves PageRank4?
and most importantly:
* Will PageRank4 bring extra search engine traffic? Let's wait and see.