SDL 2.0 has been talked about for many years but never quite materialized into a stable release. The SDL 2.0 features are covered in this article. Among the exciting additions over SDL 1.2 is a force-feedback API for joysticks, audio capture support, better multi-threading support, new audio/speaker capabilities, hardware-accelerated 2D graphics, multi-window support, better fullscreen support, and much more.
While not yet released as stable, the SDL 2.0 library has already been used by some of Valve's games, numerous indie games, and some open-source projects. A Steam Linux update already has the SDL 2.0 final ABI. Sam Lantinga, one of the key SDL developers, joined Valve last year.
The SDL 2.0 Release Candidate can be downloaded at libsdl.org.