Got the update and I'm using AirPrint with the Printopia for Mac bridge between my iPhone 3GS and my HP Photosmart C4280, which is nearly four years old. It all works perfectly with Safari, Mail and Dropbox. A great solution to wireless printing
loads to about 140mb for me then hangs and the time of download just keep increasing - set off at 5 mins to complete have aborted it twice when it's got up to 48 mins!!! Guess I'll have to leave it a while and then retry later - servers must be jammed!