Project Titan employees have a cover on their badges and pretty much nobody have access to their buildings. I know two new employees who went to Project Titan team that are heavily focused on computer vision.
I spoke to someone who worked at Apple in the pre-iPhone era, he said similar things about what ended up being the iPhone team.
It honestly just seems like a waste of time to me. That and the fact that I never see Apple employees at conferences etc. - it makes me not want to work there.
I really think that the purpose is of the secrecy is more a technique to keep focus among engineers than anything else. Knowing more than one needs to know leads to internal politics and discord. In a weird way Apple can really boast of having "startup-like" teams inside it, because everyone knows exactly what they need to do their job (engineers atleast).
Gossip and rumours don't matter. Internal politics can be about concrete things, trying to influence this or that decision etc.
If you cannot even SEE or talk about their project with the members of the other teams, that stops right there. Sure, you can rumour in the cafeteria about it.
