What makes the difference in the WinTel world is that everything is advanced, separately.
With Mac's, they release total packages--whereas, in the PC world, yes, Intel may release the exorbitant $1,000 chip, 3.2Ghz EE.
The difference is that it makes the "lower" models, cheaper--while at the SAME time not forcing a TOTAL upgrade.
Apple does not release motherboards or cpus. The closest they get to that is BTO's...but again, a TOTAL upgrade--which is very problematic--and is probably the cause of the perpetuation of rumor sites like these. Each new product is relatively expensive, representing a substantial and significant investment.
On the other hand, in the PC world, a new cpu release means cheaper prices for the older models--and it is usually a quick an easy swap (Pentium 4 2.4Ghz to a 3.2Ghz for example).
Upgrades are that much harder on the Apple side with the "a,b,c" (e.g. 1.6g5, 1.8, 2.0) model-based marketing.
*The ironic thing is, I too am waiting for something--a video card upgrade. Either nVidia/ATi will release a new card, and the older model prices will plummet--pointing to an opportune purchasing time window. Unfortunately, nVidiarumors or ATirumors.com does not exist
