Nothing has changed. The singular goal of Servo is to make a great browser engine. There are lots of things that can be done with a great browser engine. Let's talk about what we can do with a great browser engine once it exists.

The reason why you can't find an answer as to whether Servo will replace Gecko is, in fact, that there is no answer to that right now. Any sort of wild speculation as to whether Servo is going to replace Gecko is extremely premature at this point.