I find it surprising that Dusknoir and Dragonite are both still OU - I honestly don't think I've seen a single one in weeks. They are both outclassed by another pokemon quite soundly, so I'm not sure why their usage stats are so much higher than something like Porygon2, who has no better equivalent in OU.
Dragonite has light screen going for it, which means it can't be forced out by bulky waters when setting up.