We've been working on a product that utilizes a NRF51822 chip as well as WS2812B NeoPixels. Since there have been numerous posts about it here we've decided to release our code under the MIT license.
Known Caveats: While using S110 the refresh rate is limited to the radio-activity notification. When a device is connected this usually ends up being on part with the min-connection-interval. When a device is disconnected it is linked to the advertising interval.