Released this week, GeForce Experience 1.8.1. has added support for streaming to Twitch. Everyone's doing it! The integrated recording feature, ShadowPlay, can be used to live stream your games with a promised minimal hit to performance for GTX 600 and 700 Series cards.
Best of all, the frame rate is not capped. In its announcement post, Nvidia showed footage of Warframe set to High, and it looks quite good as expected. There's work to be done, sure, but talk about a nice feature for folks who have a supported video card.