Does anyone know what LED’s Adafruit actually uses for their Neopixel products? Are they related to the trusty old WS2812’s?
They are currently WS2812B’s.
(The WS2812B is a 4 pin version of the WS2812 which is a 6 pin version of a 5050 led with a WS2811 controller in it - note that all 3 have slightly different timing profiles, however). I believe the WS2812B also introduced some protections against mis-wiring power/ground/data.
Their RGBW chips are most likely the SK6818 (which is the 4 led version of the SK6812 which itself is a WS2812 clone). There was a brief period of time where some RGBW chips were sold as RGBW SK6812 (as opposed to RGB SK6812), thankfully SK wised up and changed the product number 
Sorry, I meant their newer, smaller LEDs with a 3535 footprint. I didn’t think WS2812’s came in that size (though obviously I haven’t been paying great attention).
Those as SK6812MINI’s
Good to know. Thanks!
All of the WS2812Bs that I have been getting are 3 wire, only data, no clock.
Yes - all the WS2812B’s and their clones are 3 wire. Clocked chips, like the APA102, WS2801, and LPD8806 are 4 wire.
Note that I was counting the number of pins on the actual chip above, not wires. The WS2812 has 6 pins, the WS2812B has 4.
Ahh, gotcha, thanks for the information.