I didn't say there was a guarantee. However, if it does transfer, it won't be until the next update. Not sure about the backlinks, as far as actual visible links shown on the link: command... but credit for them should be transferred as soon as the 301 is picked up. Rankings will depend on a number of factors, so that's a bit of a wildcard. -Michael
yes, it is a fact but if you want to redirect your blog to proper domain then do it after PR update and get some strong backlinks to your proper domain. you will have 3 months i think it is enough time to get strong PR once again.