It should be noted that some ebooks being sold don't as far as I know have DRM on them; unfortunately it doesn't actually state that anywhere I've seen, but then it's still early days.
Pan Macmillan contacted myself and some other authors whether they'd be happy about their books being available without DRM, and I for one said hell yes. I note that the price of at least some of the books on the Waterstones site is lower than the paperback equivalent price (there's one or two UK-published books not yet available electronically in the States going for about £4.75, less than on Amazon UK) and although they remain pricey by US standards, I don't know whether that's the result of the publishers or the differing exchange rates - the latter of which might mean such things are unavoidable.
I mention some of this not to push my own stuff 'by the back door', but because I think many of the people on this site will be openly supportive of any major publisher that makes a serious move towards producing ebooks that lack DRM. Although Pan Macmillan do pay me for something, they don't pay me to say that I think they should be commended for making a step in this direction.
if you go to the site at panmacmillan.com, they have a list of their ebooks available - some of which, apparently, are DRM-free ... except it doesn't say that. Yet.
I've emailed someone at Pan for clarification and, assuming they're not busy getting all this stuff up and running, I should hear something back.
PS -
There's an article up at the Guardian that discusses the cost of the ebooks.