I'll make sure to have everybody in this thread complaining about the good stall pokemon that are ravaging OU, not the weather abusing ones ;)
Funny,
I know I don't speak for the community, but here is what I am seeing right now as
potential problems.
Vicini:
Speaks for himself, but this guy is a beast. With sun playing a slightly larger role in this format, Vicini gets even more nuts, as outside from Flashfire Arcanine and Houndoom, and slowbro, not much can really take a V-create in the sun. This guy has no buisness being in UU.
Chansey:
With a large amount of the better fighting pokemon (Infernape, Conkledurr, Machamp, ect) chilling it up in ou, chansey does not have much that can hurt it. I am currently running one myself, and this thing is really sick. It walls a good portion of the metagame, and with the lack of steels around, can toxic stall anything not poison type itself. This might be the lack of expirence, but if it does stay around, expect this to be the swampert/ferrathorn of UU.
Kyurem:
This guy it on the same power level as the Lati twins and other OU dragons, and slipped here mainly because he was outclassed, but I feel he is too strong for UU,with the same Draco meteor sweeping powers that Latias had, even though latios did the job better. Again, time will tell.
These are the three biggest threats that I have noticed in a good portion of my battles today. I think out of the 20UU battles I have had, only two people didn't run 1 of these (and there were some who had 2, and 1 guy ran all 3). Whether or not they belong here is another story, but I see the BL list starting here.