From the BBC article on the topic:

"Does Tesco want .supermarket or .groceries?" said Graham Hales, of branding consultancy Interbrand.

"Or maybe it wants .value or .everylittlehelps. The choice is endless."

While this may address the lack of domain names now available thanks to squatters and collectors, it'll make the web a mess! It's already bad enough with some of the more exotic domain names in use, but with custom TLDs it'd be easier to just memorize the IP address instead!