First, Steefel mentions the fact that they're aiming to release another expansion this time next year, and that there will be several new books released between now and then. While this has been discussed before, he mentions the act that these books will all take place in and around Lothlorien. Does this mean we may see the next expansion focusing on Rohan? Oh, wouldn't that be amazing.
Later in the Strategy Informer interview, Steefel mentions the fact that he's been in the business for 15 or 16 years, and this is best gig he's ever had. Not only that, he says they're expanding all over the place, which should keep him busy from now "right through to 2017". If you've ever had any question on the longevity of this game, that should quench your curiosity a bit.