Now that pre-production has ended and development is in full swing, I've been tipped off to some info on TES6. You all know the drill by now -- can't give sources or anything (you wouldn't believe me either way anyway). Enjoy the read, and feel free to call bullshit and fake all you want.
The game is indeed called "The Elder Scrolls VI: Hammerfell". The team originally wanted to go with a more specific name that referenced the plot (like Oblivion) but it was scrapped very early in pre-production. The basic plot synopsis revolves around the Aldmeri Dominion reattempting their invasion of Hammerfell after the first one failed. To achieve this, a high ranking Aldmeri wizard manages to bring the Dwemer back to Tamriel via a portal to a pocket dimension. In exchange for their freedom to resettle in Tamriel, they must join and assist the Dominion with their troops and technological prowess (ie; airships, newer constructs, steampunk-esque firearms).
There are two different factions of Dwemer that wrestle over their cultural identity and the morality of assisting the Dominion, each with their own questlines. Hammerfell's native Forebears and Crowns are also present with their own questlines.
The new Dwemer tech in Tamriel is a major part of the gameplay loop. The firearms are your typical steampunk style (think flintlock pistols). To balance them with bows, they hit hard but are loud, very slow, and with ammo harder to come by.