You still need to put a brand name or trademark in front of the TLD, so it really doesn't add anything to anybody's options for registering a domain.
Nikon will want "nikon.camera", but it has no value to anyone else, if you register it their lawyers will take it from you anyway.
Neutral names, like "dlsr.camera" may be cool to have (ie, vanity), but if someone else owns "dlsr.com" and or "dlsrcamera.com", your basically sending traffic to them if your trying to communicate it offline, so they have very little practical value.
Alternative use of existing national TLD's has proven to be a niche for techies like us (.io), and failed to gain any traction with regular users, despite some pretty obvious ones (like .tv). New style tld's we already had are also barely used for other than rare pragmatic reasons (.info), or are as good as dead (.mobi, .biz).
I see no reason why these new TLD's will be any different.