"FindTheBest"

A new ereader comparison site: FindTheBest.
I haven't tested it seriously, but it seems to be advanced.
The webmaster informs me:
...we have one feature that really helps users make quick, informed decisions and that is our Smart Rating. The Smart Rating is determined by using the weighted average of 4 different well-respected expert reviews. Therefore, even if a user sorts and filters by screen size and price, they will still always be able to see how that e-Reader stacks up to the other ones.

With that and ReaderRocket.com we now have at least two such dedicated sites, I think that is indicative of how serious and solid the ereader now is becoming in our culture.
How long before it'll be the default choice, over paper books, at least in the US? Can't be long, maybe less than five years.

Other English-speaking countries are a couple of years behind, simply because Amazon (having the break-through product, Kindle) works in the US first. And the rest of the planet has the additional hurdle that they can't generally just use the existing e-published ebooks, they have to get their own publishers to publish ebooks in their own language, a process I bet can easily add 3-5 years to the whole thing.
In other words, if viewed globally, I think roughly a decade before ereaders are dominant.