Intelia: fair is to compare the highest clocked cpu on one architecture to the highest clock cpu on another. Like a p4 3.8 to an fx 57... or a dothan 2.26 to an fx 57. If you dont want to do that then you can compare similarly priced cpus to each other... Like a 2GHz dothan to an athlon 64 3800+. Since the architectures are different you cannot do a straight clock-for-clock comparison.
Now about conroe... from what I about it (that it is a 14-stage-pipeline, 4-issue core with fully pipelined execution units with lots of cache and a 1333 FSB) I'd say that it will perform about the same to slightly worse than AMD's A64 clock for clock. Of course it will probably scale higher on the clock speed since intel probably went 14 stage to be able to maintain a marginal clockspeed superiority. Now, there are a lot of unknowns that could make performance better but I think conroe will still have the Pentium M's weak FPU performance which will be somewhat made up for by its 4 FPUs.