Authority Domains

[Aviva]

So, the big thing in Google seems to be that you need an authoritative domain, and some domains are more authoritative than others. As well, certain domains seem to have a "natural" authority - like .gov, .mil, .edu.

What I'm wondering about is the .pro domain. I know it's not really well known, but that just means you get a better selection and I think it should be easier to brand.

I'm wondering if Google might think these domains authoritative simply because they really haven't been used to spam. Also they're difficult to get and quite expensive, which means it's unlikely they'll be a major source of spam. And one could consider professionals to be authoritative in their fields.

What do you think - do you think that .pro domains would get some sort of a ranking boost in Google? Do you think a .pro domain would escape the sandbox?