There's no reason this couldn't be done now, someone just needs to implement that in PackageKit and it would work fine on many distros and package managers. The backend and everything is all there, just make a drag and drop event instead of clicking an "Install" button.
That said, installation of software on Linux has been one its shining points for a long time. Package management is awesome and neither OS X or Windows offer it.
That said, installation of software on Linux has been one its shining points for a long time. Package management is awesome and neither OS X or Windows offer it.