If you haven't played MTA:DM and GTAIV multiplayer, then you're not qualified to say which is better/more fun to play/or whatever.
Dan Houser said the console versions WILL have multiplayer. Since there has been no mention over a PC version, I don't know why everyone is getting so worked up. I have no rift with MTA and have been waiting and supporting it since Blue was announced, but you shouldn't judge it based on how other multiplayer platforms perform (cough) SA-MP (cough).
At least they have released something, you know? That's more than MTA devs can say at the moment.