So do they do like... expansions or something?

Not to sound like a complete idiot, but Skyrim is the first Elder Scrolls game I've cared enough to actually play through. I LOVED Morrowind, but only enough to get to Balmora and make spells to jump across the world and shit, not nearly enough to care about the story. I HATED Oblivion, and I can't honestly explain why, but I hated it. Skyrim is amazing, and I thoroughly enjoyed it. Since I haven't payed attention to previous TES games, I'm curious, do they do expansions like they do for Fallout? If the only incoming DLC is gameplay mechanic changes and shiny crab armor, I probably won't stick around.