Comment 7 for bug 376603

I have just discussed this with the Ubuntu One developers, and they are working on an even better solution: getting their software into Ubuntu's Main repository. But the general point holds -- if you want your software to be installable in Ubuntu without warnings, you should (a) get it into an official repository, (b) get it into an already-whitelisted repository (e.g. the Canonical partner repository), or (c) apply to get your own repository whitelisted. I don't think Launchpad should do anything special here, apart from making the PPA-adding instructions easier to follow (bug 338256).