Uh... you do realize that there are features stripped out of the DP that will be brought back in the official Cyan release? BT 4.0LE for example.
No. That is not true. Nothing was "stripped" out of WP8.1. Black, Cyan, Denim, etc... are Nokia (now Microsoft) specific firmware updates with some Microsoft specific goodies baked in. Bluetooth 4.0 (aka Bluetooth 4.0LE), is a hardware standard and therefore separate and distinct from the OS. Therefore, Microsoft will include that into Cyan NOT the OS. The same for the HTC. The HTC M8 also has Bluetooth 4.0, but it with "aptX", so HTC has to provide its own firmware for the hardware. Also, non-Microsoft devices do NOT get Cyan; but they do have their own manufacturer specific goodies that are not available for us Microsoft users.
To clarify my previous statement. As of right now, people who are running WP8.1 DP are running the same (actually a more updated) version that is running on the HTC M8 for Windows. If Microsoft were to release Cyan to us via the developers preview program, then we would be running the same version of Cyan (since there is only one version) that will eventually be released by Verizon and has been released on other carriers.