http://www.seologs.com/pr-dc-check.html put in the url www.solarsystem.com I see 5's 6's and 7's Weird! I don't think there's a page rank update going on, this is the only site i cannot duplicate the problem.
I see alot of pr fluctuations latelty. Check also mcdar.net, probably the start of a pagerank update or something. Give it some time.
Yea, I have been seeing variations for a long time. One of the datacenters shows PR3 for blazemp.com, which it hasn't been PR3 for over 5 years (except for a couple months after an issue with Google).