It gives the system more stability if the package data (including package conflicts, etc.) is fleshed out. Plus, it helps the users know what everything does, helps system admins fix broken things easier, and is just plain old better developer "best practices."
As I mentioned in another thead, I'm willing to help out by pulling off and editing the original package meta data from the standard Ubuntu repositories, and help build a conflicts database to ID packages that don't play nice with each other. But I don't code, and I'm probably not going to try rebuilding any packages, so it'll be up to the developers to make use of it.