That's pretty much it. The LED starts flashing when you hit the first level warning voltage, and then it just starts to descend when it hits the second level. The descent isn't slow but it's not super-fast either, it seems to be the same speed as it descends when doing a full RTH. Once you've seen it happen a time or two you'll be prepared for it.
I'm not 100% sure on whether it shuts the motors down after a few seconds following auto-land for battery. It might, but I always kill the motors right away myself.
I've found that it does a pretty good job of making a smooth descent, the touchdown can be a little bouncy sometimes though. But when landing on the grass I often just let it bring itself down and settle on the ground and all I do is kill the motors after.