You can download it here.
Highlights of this beta include: * warmer colors, down to 2700K * f.lux for Philips Hue * support for calibrated monitors * movie mode (partially disable to watch a movie) * disable until morning * screen warms as you dim it * fixes for Intel chipsets * fixes for Windows 7+
Check it out and let us know what you think.
If you have f.lux installed, it will update automatically.
If you have an older version, you can quit and relaunch the f.lux app to get the new update.