There was a few discussions on the rsync mailing lists about how to handle compressed files, specifically .debs I'd like to see some way of handling it better, but I don't think it'll happen at the rsync end. Reasons include higher server cpu load to (de)compress every file that is transferred and problems related to different compression rates. see this links for more info http://lists.samba.org/pipermail/rsync/1999-October/001403.html
johno
