Odd, because you strike me a through-and-through Mac user:I just switched back to a Mac laptop because of the Air.
If battery life is the main concern... then maybe. Otherwise the MBA will be a way less frustrating experience.
The reason I quote that is that there could be other reasons for choosing the X300 over the Airbook, why don't you mention them? I don't get that. To me, that makes your statement about being a PC consultant rather suspicious. Unless, of course, "consultant" simply means "sales man" – quite a difference.
Anyway, let's see if we can find other "main concerns":
Matte screen: A definate plus for a pro – especially if working with pictures (I'm not, I just do audio). I will not buy a computer with a glossy screen – especially not a laptop.
Better keyboard: If I were to write a lot, I might choose the one with the best keyboard, no? That, to me, is the Thinkpad.
Or how about WWAN/Wimax? You see, as there are no expansion ports on the MBA, one might quickly run out of options for this sort of thing on the MBA. Some people (at least around here) actually use those things to get work done.
Or, how about someone using an app that needs a dongle (some of us do) or otherwise need more than one USB port. With the Airbook, you're pretty lost. Perhaps that could very well be yet another "main concern".
Another "main concern" [sigh! It seems endless], could be someone who actully needs to burn or run a cd from time to time, but are not willing to take the weight penalty and clutter offered with the "solution" from Apple (i.e. external).
I think, that with all those "main concerns", one could easily turn your pseudo argument around and say "If your main concern is watching movies (which looks best on a glossy screen, I admit), or your main concern is having a backlit keyboard and having a place to plug your iPod into", then the MBA is the computer for you.
Having owned about 8 ultraportable (3 lb or less) Windows based laptops (all without integrated optical) I can honestly say this MBA is the nicest, best built, easiest to use laptop.
Sorry, but if my experiences with apple's hardware in the last four years or so is anything to go by, the build quality leaves much to be desired. Yes, they look nice and they run my favourite OS, but that's about it. But then again, they're silver. Boy, am I tired of anodised aluminium …
Propably. But to many people it will be much more useful than the MBA: the MBA may have a quicker processor (as far as we know), but it packs nothing. Most people can get their work done on a little slower computer, but many won't be able to get started, if they can't plug in, or otherwise are inhibited.Lenovo is not bad, but that ULV processor will make it slow!