I have an old Laserwriter 4/600 which uses a LocalTalk - Apple adapter to print out of OSX. Seems that Parallels can't do this for other OSs because there's not AppleTalk support built in - consequently I can't print out of Windows Vista and any version of Linux. I don't think Vista Home has any support for AppleTalk - it would be great to have Parallels provide this layer of support.
You can always print to a PDF then transfer it over to the OS X side, perhaps write a perl script to periodically print out the contents of a folder where you would save the print jobs to then delete (or archive) those PDFs. I doubt Parallels will integrate AppleTalk as it sorta is a dead technology, I think that their time will be best spent elsewhere.
