You got me there, my rational side agrees with you completely. The only performance differences are FSB/memory speeds. Santa Rosa's frequencies are 266 / 333 (CPU / RAM), while the desktop platform runs at 333 / 400, otherwise processors are practically the same.
But while the performance difference may not be big, it's just the feeling you're not getting the latest and the greatest that I'm missing. Apple used to define the technology, (their notorious LetsLoseTheFloppy move comes to my mind) they often used bleeding-edge stuff in their machines and so on.
While PC users are currently enjoying brand-new-just-out-of-the-factory 1333 mhz quad pumped FSB processors on P35 motherboards with DDR3 support, the new iMac has C2D chips comparable to the ones we've seen on desktops a year ago (of course they are the newest on the laptop market, but that's just an excuse in the eyes of an average customer - iMac is a desktop machine and should be treated that way).
But I'll stop there. Must be just my sensibility
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