That's because the X301 is far, far better than the original X300. They improved the screen and a lot of other small details. It's almost, but not quite, like the difference between rev A and rev B Airs.
Actually the X300 and X301 screens are identical (I have had them both) and there are only minor changes between the two models. The processor got an update and there is DisplayPort output along with the newer Intel video chipset. The X300 was pretty much fine on the first go.
The screen on the MBA is a bit washed-out like the MB. The MBP screens on the other hand are quite nice. X300/301 screens are quite crisp and sharp - the viewing angle is not as nice as MBA and colors are not as good. It's wonderful to have 1440x900 on a 13.3" screen and there is real utility in the 5 hours of (real) battery life I get with full brightness, wifi on, and heavy use of the machine. The ergonomics of the X300 are simply excellent.
Again (I feel I need to say this), I am a major Apple fan. I use a Mac pro as my main machine attached both to a Cinema display (and Dell monitor). I have an iPhone, Time Capsule, and several Airports. I drink plenty of koolaid and even own the stock.
It just seems that many Apple fans are more about the cult than the facts. There's room for a balance. I just got rid of my white Apple keyboard after realizing that although it looks great - it simply isn't as ergonomic as the Microsoft curved keyboard I replaced it with. The Apple mouse sucks too while I'm at it.
The anti-Microsoft, anti-Apple, anti-XXXX stuff is boring - there's some good stuff on all sides and competition is a good thing. Windows 7 is quite nice - especially the new dock - and I enjoy Google Chrome more than Safari - I think it is more Mac-like
