Tuesday during the NFL season is traditionally when power rankings are released so the media can tell us what they think about the state of the league. Everybody and their brother (including me) will come out with rankings and their spin on them. For the most part they are all fairly subjective and riddled with our own biases.
One set of rankings are not really power rankings, but do provide a more objective look at the state of the league. Football Outsiders uses its DVOA stat to tell where each team stands in the grand scheme of things. They also have a state called DAVE, which combines DVOA with preseason projections to tell the broader picture of a team. A team playing over its head through the first two weeks will have a higher DVOA than DAVE rating.
FO released their week two ratings and they currently rate the San Francisco 49ers No. 11 in DVOA and No. 15 in DAVE. They've played a bit over their head so far primarily based on how well they hung with the Dallas Cowboys. These ratings don't mean a whole lot when you blow a lead like that.
FO rates the Oakland Raiders No. 15 in DVOA and No. 25 in DAVE. The Raiders low DAVE is based on a pretty abysmal preseason projection in which they had the Raiders winning five games. There is still a lot of football to be played, but the Raiders have not looked like a five win team thus far.