Well if you look at the page, in small print it states "Product specifications may differ from country to country. We recommend that you check with your local dealers for the specifications of the products available in your country."
Well you can buy the N43SN in Asia, China/Singapore, have been able to do so for a few months now.
But you are correct I don't understand why Asus don't sell this laptop in the UK/USA, its utter madness!!
I actually paid for an i7 N43SN from a Polish website http://www.x-kom.pl/szukaj/asus_n43sn they are fine, i transferred money via bank transfer, crazy thing is from the UK it was going to be cheaper to Fly and collect it rather than get them to courier it out.. go figure....
Anyhow, I just heard from them on Friday and after 3 delays in shipping, they said Asus yanked the i7 model because they couldn't get blueray drives because if the earthquakes in Japan causing shortage in supply.
Needless to say I am gutted, I could swap for the i5 model and upgarde the CPU myself but i'm over it, i'm considering a refund, perhaps ill get a Lenovo Ideapad Y470 (same spec as N43SN) or Dell Alienware M14x (better spec GT555), who knows... seriously.... I give up.