I've read some benchmarks with all of them.
First of all, don't get the 'e' models. They're meant for blade servers, and so they don't have power management. In a notebook, a few ms to bring the drive up a few power levels isn't a big deal, but in a server it is. The 'e' models aren't going to get you any tangible performance benefit, but will suck more power.
As for the various models, as a comparison the average read speed of the 7k60 is about 35MB/s, and the 7k100 is about 40MB/s
for a comparison, the 5400RPM Seagate 120GB drive is 32MB/s, so while increasing density does indeed increase speed, the rotational speed is still more important for raw transfer rates. You are not going to get a faster transfer rate by going from 7200 to 5400 based on benchmarks.