AnandTech have managed to get some new info on Bulldozer architecture, and more especially on the implications of the integration of two integer cores (see this news).
First of all, building in this second core is reported to be costly in terms of transistors as it will necessitate a 50% increase in die area. Obviously this is less than doubling the size of the die, which is what you need to double everything, but a good deal more than HyperThreading that only requires a 5% increase.
Secondly, according to AMD the performance benefits of this second module will be high – it believes 80% of normal server workload is integer operations. Good news then.
All this will have an impact on how AMD counts cores. AMD considers Bulldozer to be made up of two cores as it is made up of two integer blocks (and this even if there is just a single floating point core). We do understand the reasoning behind this, but we reserve our judgement as to the practical impact for a later date.