Bear in mind that most people who're just starting with ebooks won't even think about looking abroad for ebooks and won't want the hassle of converting them. I was thinking more that Fictionwise books tend to start off at $20-25 when the hardback version is out, which isn't all that much different.
But personally, I doubt I'll buy from the Waterstones store much if at all, not least as I still don't like my books being tied to one device, which although ePub is nice, with the DRM they still are as no other device currently supports it
