As a "power user" who sold my MacBook Pro 15" to replace with a MacBook Air, I can tell you that I get better performance from the MBA than I was getting from my MBP. Granted, my MBP was a Core Duo 2.66. I know that a new SB MBP would offer better performance. I own a 27" iMac i7, with 2TB of HD, and 16GB of RAM. And I love it. But my MBA is the best computer I have ever owned.
I wouldn't welcome the switch, personally. We're just now getting beyond the transition to Intel, and Apple doesn't need the FUD of incompatibility claims out in the wild.
I believe that if it's true, it's strictly laboratory stuff for now. At least 2-3 years from being public.
That's because the Air has an SSD. Throw an SSD in your old Core2Duo MacBook Pro and the MBP would be faster. I can understand if you prefer the Air, it's very portable... but it ain't faster than an '09 MacBook Pro. It's the SSD that's making the difference.