Recently in Germany there was a cross-distribution meeting among the major vendors (Red Hat, Canonical, Novell, Debian, Mandriva, etc) to discuss a common application installer for Linux and one unified application store / market-place. The goal would be to have a common user-interface for application installation, how/what meta-data to use, determine a defined protocol for non-static meta-data, and decide what meta-data to share across distributions. Fortunately, this was a very successful meeting.
I made a quick post here: to see if anyone knew anything about it and whether it would be included in 11.10.