Android is gonna have to fight the old war of OpenSource platforms that go commercial (a fight that has been won only very seldom in the past). If it succeeds at that, its future is going to be very bright. Cydia will never be as popular and/or successful as the AppStore. But then again, it never was supposed to be. Cydia is supposed to be an open platform welcomming any kind of developer without restrictions and/or fees. The idea itself is meant for an outsider-position. Saurik is doing an awesome job at maintaining the Cydia store, but his much more important work consists in bringing *nix software to the iPhone platform. Cydia is only one of these advantages ;-)