SailfishOS is a definitely slick and usable OS offering some cool features and a bunch of new stuff.
Check out the video for some more info and video footage of working features:
If you're curious, though, you can give it a try!
To install the ROM, you have to be running on the CyanogenMod 10.1.3 ROM. After that, just simply download the package, wipe out the data / do the factory reset, and flash the zip.
The entire installation procedure can be found on the XDA thread HERE.