I think there is good value of one-word domain name, whether it is on .com, .net, .org or .info extension.
I would say that if you find some one word domain then you should register them if they are good word.
But I thought they are not easy to get most of good domains are booked already and if somebody want then they have to pay much for that. But if they are easy to get then one should use these.
Yes, they are not easy to get them, but you can find it from drop cachers, where good domain names are still dropping, of course you have to go through auction, backording etc.