oh Sh*t look at me im on page 26
ok but really i need to know what is OU in the new Japanese VGC now cause i see alot of Mewtwo's and as MattJ said Choice Scarf Kyogre
Ho-Oh and Groudon, Kyogre and Palkia, Kyogre and Dialga, Kyogre and Mewtwo and Ho-Oh and Giratina-A seem to be the commonest uber combinations from what I've seen. Kyogre is the most-used, with Ho-Oh closely following (interestingly) as well as Dialga. Mewtwo, Giratina-A, Groudon and Rayquaza are seeing sporadic use too with the very occasional Lugia.
Kyogre is almost always run as bulky offense @leftovers (I've seen very few scarfed ones) as is Ho-Oh, which often has jolly substitute/roost/sacred fire/brave bird@leftovers as a moveset. Palkia is pretty much always straight-out offensive but you do get the odd substituting one. Groudon and Giratina-A too are regularly bulky offense and not really ever anything else. Mewtwo and Rayquaza are in the same boat as Palkia, being simple offensive pokémon (though specs Mewtwo is uncommon). Dialga is virtually always bulky with trick room. Lugia is pretty much just a bulkier and less versatile Cresselia also, and I've never seen one do much in a battle.
With the non-ubers, tried and tested favourites like Smeargle, Metagross, Ludicolo and Latios are still as popular while other like Garchomp, Zapdos, Salamence and Gyarados have fallen a lot in popularity. Cresselia is very mildly popular as a partner to Groudon, as is Shiftry. Water spout Octillery and Blastoise are seen occasionally but rarely and when they do, they tend to be disappointing.
So yeah that's my quick analysis of the last few months of Japanese VGC. I've been watching a lot of battle videos (about 50 in total I would say) and that's what I've seen.