NVIDIA has been upgrading their GeForce Experience just about once per month, on average. Most of their attention has been focused on ShadowPlay which is their video capture and streaming service for games based on DirectX. GeForce Experience 1.8.1 brought streaming to Twitch and the ability to overlay the user's webcam.
Until this version, users could choose between "Low", "Medium", and "High" quality stages. GeForce Experence 1.8.2 adds "Custom" which allows manual control over resolution, frame rate, and bit rate. NVIDIA wants to makes it clear: frame rate controls the number of images per second and bit rate controls the file size per second. Reducing the frame rate without adjusting the bit rate will result in a file of the same size (just with better quality per frame).
Also with this update, NVIDIA allows users to set a push-to-talk key. I expect this will be mostly useful for Twitch streaming in a crowded dorm or household. Only transmitting your voice when you have something to say prevents someone else from accidentally transmitting theirs globally and instantaneously.
GeForce Experience 1.8.2 is available for download at the GeForce website. Users with a Fermi-based GPU will no longer be pushed GeForce Experience (because it really does not do anything for those graphics cards). The latest version can always be manually downloaded, however.