Although Warlords of Draenor has been out for a while, players had to wait till yesterday for Highmaul, the expansion's first raid, to go live. Seven top guilds, with the veteran Finnish super guild Paragon leading the list, already rushed through it without any trouble.
We can say Highmaul is a relatively large raid with its seven bosses (with two of them being optional, and some of them with some really funky mechanics, such as the Twin Ogrons in Method's video below). Not as big as Ulduar, Naxxramas or Icecrown back in the old days, but you can have fun with 7 bosses for weeks.
According to WoWProgress, this is how things look at the moment. You can see the guild names, their faction (red = horde, blue = alliance) and their progress on the bosses. If you've followed WoW raids in the past you can find some familiar guilds there. But not everyone. Where is Blood Legion? Or Method? Those guys are always on top.
They all did it on Heroic difficulty. It's the currently hardest one, but Mythic will be even harder when it opens next week. We have to wait a few more days for that, and probably that's when all the missing top guilds will show up.