I don't have a Kindle, but a family member does and LOVES it. She carries it everywhere and it has allowed her to thin out her bulging hard copy book collection, which has created some much-needed shelf space. I don't know how they are in the UK, but the large sized Kindle here is not backlit. This makes for a more book-like and less computer-like reading experience, so I'm told.
I have some children's books listed in the Kindle bookstore and one science fiction short story. They haven't been reviewed yet. I sometimes offer them for free in hopes that someone leaves a review - positive or negative, I don't care; I merely have a writer's insatiable craving for attention. I'm crestfallen when nobody ever does. But I assumed people just read and forgot them instantly. Now, reading this thread, I think I'm getting a clue - people download free books and keep them available in a library but don't necessarily read them. Makes all too much sense. I'd do it myself, alas, if I had a Kindle or any compatible equipment.
I do believe ebooks are where we're headed. It's sad for what we're losing but encouraging in the sense that information and entertainment bottlenecks are disappearing. The publishing industry has been stagnating for almost forty years even while it's commandeered creativity, becoming less and less willing to take financial risks on the young, the new, the unproven. Now with self-publishing venues, we're seeing for the first time since the Golden Age of fiction indie writers getting a chance. And while most of them are ****, there are a few stars - just like in the Golden Age! (Did you know that back in the day, Robert Heinlein bought a car and paid off his house with his SHORT STORY earnings? It was a living. The publishing industry has not been able to offer that kind of living to the bulk of its creators for decades. This is a product of the extreme expense of supplies and distribution of print materials - a dilemma that does not exist with electronic publishing.)
So anyway, what I'm saying in my long-winded way is that there is a huge variety of material available on Kindle and nowhere else - not just mainstream material, but the new, the different, and the trendy. Also on Smashwords and other online ebook publishing venues. And again, much is **** but not in any ratio much different from traditional publishing. :|