Yes I wanted to add some easter eggs was there was too many important things to fix. Now that the software is more reliable I can start to think of simple easter eggs that will be in the final version. There will be some, be sure of that, but you may not know about them
Concerning "hidden features", as GFD and Fraisie said, it's more about adding another level of customization. There is maybe between 10 and 15 options that are not available through the Preferences panel (a simple example: the timestamp format used in the Event Viewer).
It will be documented sometimes, or check the forum, sometimes I post some information about specific values.
Patchou