I remember when Smogon unbanned Deoxys-s for a bit. Although it didn't quite revolutionize the way people built teams as Garchomp (who should be on this Ubers list, shouldn't it?), a LOT of people used it, and quite successfully I might add. I remember it to be one of the most annoying leads and pokemon to deal with in general, and while being annoying probably doesn't grant something uber status, it sparked a number of special defense oriented pokemon such as Drapion (or even Bulky Ttar) to become semi-staples.
In theory, I think OU in general may be able to handle Deoxys-S, however referencing an old Smogon defenition of uber status: "a pokemon that very heavily influences the OU metagame and the creation process of every team" or blah, something like that.
I guess what I'm saying is that if it becomes TOO MUCH of a hassle to deal with that people will have to come up with two or three pokemon combinations to effectively get rid of it, it may have to be Uber.
Of course, this means that it's up to the testers to verify whether or not this is true.
With all the hard-hitting pokemon, I guess Deoxys-D would be reasonable for OU, but again, I'm leaving this up to testers as I've had no experience with it.
Deoxys and Deoxys-A though are a different story. Not even the pseudo-legendaries of OU have the brutal combination of attacking and speed stats, with excellent moves to boot. I may be missing something right now, but at the top of my head I can't think of any way these two will not be able to absolutely dominate OU.
Wobb is another one that was tested in the past and remained in Uber, and even with this pretty much new metagame, no one can deny the sheer usefulness/destructiveness of Shadow Tag, which, with correct prediction, essentially nets a free kill (at least one a game.)
Just my two cents.
