IdTech 6 seems to have been introduced to zero fanfare yesterday. It sounds like idTech 6 is just idTech 5 with Megatexture issues solved. id engines have never taken a back seat but this time around they didn't seem to care about the engine.

Reasons for naming it idTech6?

Well I'm guessing because they want to get rid of all the public views attached to idTech5's Megatexture issues.

We will never know without knowing everything that has changed since the Tech 5 engine. Just because they didn't put the focus on the engine doesn't mean nothing has changed.

id Software's engines weren't even called idTech until idTech5 and the Doom, Quake, Quake3 and Doom3 engines were retroactively dubbed idTech1-4 to match. So the number is pretty much meaningless.

Did you see doom 4 live play through? I have yet to hear any one talk about the graphics.

I didn't and exactly my point. No one, not one person said anything about the graphics in the game

The number is not meaningless. It has some value from a marketing and development perspective. It signifies changes were made, and I'm sure since Rage a lot of changes have been made but are they worth a complete number upgrade or is it just for purely for marketing reasons

I find it a little disappointing that nobody has mentioned anything about the technical observations of the Doom reveal.

The closest would be that PC gamer mentioned that there were many demons, and fatalities had similar features to Sniper Elite i.e. some anatomical substance I would assume.

A lot of detail, many iterations on-screen, this could be indicative of some kind of voxel tech.

Though like you said nobody has said anything about their technical observations on the game and it is difficult to assume anything else than a technically similar engine in light of this.