Performance/watt/$
To conclude the opening presentations, AMD stressed that the key metric it thinks should be used to assess the desirability of a server processor is performance per watt per dollar.
In other words how much are you paying for your performance both in terms of money and in terms of power consumption - which also amounts to money, but with some green kudos thrown in too.
So what you want is lots of performance at low cost and using little power. AMD thinks it's achieved this but, as ever, its offering will be judged against what Intel has to offer. Intel has a massive range of server processors covering a broad spectrum of speeds and wattages. It will be up to customers to decide how these compare.