What are they using to benchmark single-threaded performance? I don't think it's good to state that without clarifying what is the task being run. You could have a benchmark that increments a number in register. Since add/increment runs in a single clock, a high frequency CPU (Pentium 4 at 3.8Ghz?) would win over a wide core with great memory bandwidth (M2 at 3.7Ghz). Technically, that's a greater single thread performance, but not really applicable to the real world.
If it's over a variety of tasks and/or in a task that's similar to real world computation, kudos to them!
If it's over a variety of tasks and/or in a task that's similar to real world computation, kudos to them!