You can also check it at http://www.seologs.com/pr-check/pagerank.html It seems to check out there as well.
I don't know if this is right. My understanding that page rank is being updated every 60+ days. I have got a solicatation via PM for a domain that I checked it and it was two days old back then it it was PR6 http://checkpagerank.net/index.php?.......G&links=1 I have checked the domain with different tools including google toobar and it was PR6. I would love to know how that was accomplished!!! now the domain is 12 days old...
The pagerank is valid, BUT.... When a domain is dropped and reregistered it will NOT hold the Pagerank on the next google update!!