With the original EEE PC at almost half the price on Expansys (£159) and the aspire one available at around £240 I don't think this will be the success many had hoped.
That said it could compete with the XP aspire one and the EEE PC 901 which are both above £300 on the same site.
Shame about the delayed Ubuntu version, personally I feel that an XP license is not cost effective on that kind of machine. My wife bought an XP EEE 900 and I bought a Linux Wind (on which I put Ubuntu) and my machine performs much better than hers. Pretty much all the Linux apps run fine while many of the XP apps seem to struggle at times.