However, the argument that a new MBP would steal MBA thunder is, I think, closer to the mark. Apple do seem to put a lot of thought behind the timing of their releases and a new MBP released now would be asking for column inches comparing the two.
I would have to disagree if the only updates are penryn and the new MBA multitouch. Im sure Apple would be quite happy to let the +1000 people on this website alone who are desperate for the update go online and buy them when they hit the stores... Thats a nice quick $2.5M off the bat.
Thats what they did for the Mac Pro.
Its all about supply and demand.
The have demand for the new MBP.
I dont believe they do yet for the MBA - thats why they are spendin $$$ on MBA marketing and advertising.
Cheers
M.