For my main site, and it's subdomain, I had a pr increase of one, from 2 to 3. The subdomain is still 0. I had links to the main domain it from DMOZ, wikipedia and lots of pr4 sites. A great number of backlinks. On the other hand, like 2 months ago, I bought cedik.info The site was down more than half of this time, I didn't manage to do enough posts and I only promoted it trough putting it on my sig on 3 forums. And now, I've checked it on 2 sites and it has an amazing pr3 It must be a mistake, I wait now for google to show me an pr 0 to it when the pr update is complete
Of course it's not accurate. why? Because Google employ graduates who battle each other to come up with the most complex algorithms which no one really understands and as a result the output never makes any sense!