Anandtech benches Nehalem

[JumpingJack]

That's more or less correct. Most software today is multithreaded to some degree but most of it also scales very badly to 2 threads. A smaller percentage scales well to up to 2 threads and some select software scales to 4 threads and above.
I can confirm that Photosop is not fully multithreaded. You have to keep in mind that Photoshop is really not a single program but a suite that includes and integrates a wide variety of image manipulation programs. I use at work and in the operations that we use the most CPU utilization does no go above 50% on the E8400 in that PC.
As for lame the MT version is no longer beeing developed and is not recommended for home use. It's not really surprising that Intel's compiler does better than MS'. The compiler MS makes is utter garbage. On iTunes i think he meant that encoding is not multithreaded.

Photoshop is multithread... does it spawn 4 threads at every task, every time ... no... but it is compiled multithreaded. Software is compiled with one executable (generally), external functions are available through linked libraries -- photoshop has one compiled exe and loads all the libraries at load time. The 'wide variety of manipulation' programs as you term it above -- these are called functions in programmer terms ...

I just posted a screen shot of a conversion (this is encoding) showing iTunes multhithreaded....

Jack