Something I haven't seen discussed: how are web browsers going to handle somebody typing a generic keyword that is also TLD into the address bar? The chrome-style omnibar that every browser has since adopted is predicated on the fact that URLs are fairly easily recognizable.

But if amazon owns "books" and hosts something at http://books/, should browsers navigate to Amazon whenever someone attempts to search for "books"?

[Actually, is it even allowed to host A records directly on a TLD? I've been reading through RFCs and haven't seen it explicitly disallowed, but nobody seems to have done it with a currently-available TLD.]