One of my site was having PR3 before this last PR update.At that time it was hosted in US Server.Now its in UK server.But the PR seems to be PR0 ?
If the web pages URLs did not change then your Pagerank would not be affected. Just by looking at your signature text descriptions I'd bet you recieved a paid text link penalty from Google.
My dear friend If you have change your hosted server from US to UK have to done 301 permanent redirect. If no then do it and then wait for the next PR update everything will be Ok. Even if you change your URLs and if you do 301 permanent redirect then also your backlinks will appear for new url with same serp postion Cool Mate and Enjoy your day