No, I have upgraded to captain in the Boeing 767 & 757 over the last year after being a 777 FO for over 6 years. It would be nice, however you are still not the final authority as if you were to divert; have an emergency, the first thing one would do was to wake the Captain up first to plan your next step.
I am a crew member w/ a major US airline is
OH, and all of our pilots on the 777 are Type Rated. If you did not sign the release w/dispatch or the Company, you are not the captain.