You have to look at little bit more forward, rather than envision that the changes will be CPU or RAM related.
The biggest change will be the inclusion of a glass (or other material) touch sensitive surface in lieu of a keyboard. This will allow inclusion of all kinds of 'widgets' on the 'keyboard', including keyboard customization, etc.
So you would be able to change key spacing, or perhaps include keyboard layouts from other manufacturers (eg the infamous ibm thinkpad keyboard), and so on.
After reading this same thing in the other thread, I wasn't going to say anything but after seeing it written here for a second time, I have to tell you-----you are going to be MASSIVELY disappointed when the next Air comes out, if it even ever does.
Amazing how update after update after update by Apple people still expect them to deliver the moon and then some, and then update after update after update you get lackluster updates, and everyone complains.
Here's what you'll get:
HIGH END:
--2.4 GHz C2D
--160 GB SSD (256 *maybe* but doubtful, Apple won't give you a 100% hard drive space increase overnight)
--4 GB RAM
--GPU, who knows who cares, something lackluster, either continue with an outdated NVIDIA or switch to an outdated ATI 4xxx
--Glass trackpad
--Garbage screen with lines
LOW END:
--2.26 GHz C2D
--160 GB HDD
--2 GB RAM
--Same GPU as above
--Glass trackpad
--Garbage screen with lines
The only thing in my prediction I'm uncomfortable with is the same size hard drives in each, but I really don't think Apple will give us a 256 GB SSD. Hell, for all I know we will get a 160 GB SSD in the high end, and be insulted with the retaining of the 120 GB HDD in the base model.
Personally I think the Air is going to be EOL'ed soon. Haven't heard so much as a peep on updates, it's design is long in the tooth and dated, and it gets one back corner spot in the store if it's lucky.