Didn't seem realistic to me. When I talk to people I don't brag, boast, joke, and threaten them at the same time to earn their friendship/hatred.
I would've liked Skyrim's sysytem if it was actually used, and made a real difference. Oblivion's system may have been less realistic, but at least you got to use it, and it made a noticable difference. And I liked being able to see how much people liked me, instead of just using it as a tool to move quests along.
Oblivion's system lacked complexity, but I think they were on to something at least. It was better than their previous system in Morrowind, which was a game-mechanical nightmare. Unless you had the patience, Speechcraft was impossible to level up in the beginning of the game. With the minigame in Oblivion, they at least made it pragmatic. However, they should have expanded on it and made it more complex. I think the solution they made for Skyrim was stupid. The Speechcraft part of the Speech skill has been reduced to a few dialogue choices. I find myself not caring about the Speech skill in Skyrim, whereas in Oblivion and Morrowind, it was always one of my favored skills.