I'm not a huge fan of the PR system, but here is why I do see decent justification for its existance ... I'll use vehicular engine analogy since there are a bunch of car buffs here.
I'm using a very simplified model of a processor performance, FREQUENCY * IPC = processor performance as analogous (in a philosophical way) to RPM * TORQUE = power. FREQUENCY and RPM in a way represents the # of events occurring in a given amount of time, and IPC and TORQUE represent the amount of "work" that can be done per event. Of course, in a car, measuring power is relatively straight forward, and at the very least is shown to be exact theoretically. There is no theoretical bases for something like this in a processor (as of yet anyways). However, back to the analogy ... imagine if people sold performance vehicles based on RPM. So, Honda comes out with a "new" high performance 9000 RPM engine and says look, we have the highest RPM engine! Well, the Corvette (stock anyways) does not rev to 9000 RPM, so does it make it a "weaker" car/engine? Well, since the Honda has peak power at 8300 rpm, it's torque is only about 152 ft-lbs. The Corvette, on the other hand, has a torque of 355 ft-lbs. SO, while it's true the Honda can achieve higher RPMs than the Corvette, the Corvette has a much higher overall power. So, a cheesy "PR"version for a Corvette would be like a "13993+" S2000
The best solution would be to have an "unbiased" performance metric - but in the processor world, that would be impossible.
BTW, a food for thought. Where would the world (or just the US hehe) be without "high performance" race cars? It'll be less fun, but I don't see too much change in society. Now, where would the world be without heavy duty diesel engines ... LOL, it'll be really screwed up! How do you think the really nice INTEL and AMD cpu, groceries, mail, ... practically everything in life, get from the factory to the retail store? It's not just trucks, but many ships and trains use diesel engines as well. AND, how well do you think all these really cool exotic cars, mentioned in this thread, will do trying to pull a 10,000 lb trailor (not to mention 80,000+lb trailor)? And do it with 15,000 - 65,000 mile oil drain intervals, a 300,000+ mile no major engine problem even when the power of the car and the truck is the same! So, just like in cars and computers (and everything else - Sir Mix-A-Lot comes to mind too hehe) there is not such thing as one size fits all (or one benchmark).
Peace