"Frank Ocean sounds like what most people would consider r&b, but to put it in a bracket like that really wouldn't be fair. Personally, I just think that's he writes smooth songs that make you want to make romance/fuck, and the beats are fuckin' insane. He goes in over The Eagles, Coldplay and even MGMT. It's a sound that is reminiscent of old soul tunes, but is also firmly entrenched in modern/future r&b. I believe that they refer to this kind of music as timeless. Frank Ocean bleeds that Casanova swagger.
The description on the OF site pretty much nails it, though.
Smooth Ass Music About Bitches, Relationships And Being A Rich Young Nigga…But In A Swagged Out Way. Wolves Know How To Sing Too."