I like Gothic 3, but prefer Oblivion mostly because of the universe & lore. The Gothic world doesn't draw me in as much since there's hardly any lore or information about history, gods, etc. at least not comparable to Elder Scrolls.
Also, what bothers me in Gothic 3 is that there's almost no women around. The number of women I saw in the game I can count on the fingers of my hand.
Anyway, I'm playing Fallout 3, Storm of Zehir & Velvet Assassin.