I don't want to get off the topic entirely, but I'm just going to paraphrase some other threads regarding OU vs. Uber...
Early DP - Remember when T-tar was almost banished to Ubers? Hypothetical consequences were thrown around - one was to ban Cresellia as well, because without T-tar, Cressy would feel free to wall just about everything.
So, if Deoxys is re-banned, what would happen? Garchomp would also be banned, as it could set up much easier. T-tar might be considered for ban (and Cresellia as well). After that, Salamence would sweep much better and would be consequently be banned.
And soon, all of the OUs would be relegated to Uber, and we would be having UU pokemon ranked as OU. Does this sound right?
To counter my above statements, many would contend that Garchomp usage would decrease. After all, Garchomp usage apparently shot up after the introduction of the Deoxys was realised, right?
Feel free to implement this plan: Ban Deoxys, and see if Garchomp would still be a monster in terms of usage and ability to counter. If Garchomp usage stays high, re-introduce the Deoxys.
I would also like to state my understanding of grounds to ban to uber. Remember, this is paraphrasing, not actual words. I'm hoping I'm not being a douche...
A pokemon is only to be banned to ubers if there is no counter. A counter is defined as one that can switch in without taking a huge amount of damage (either by an item removal, or actual attack damage), and either scare it away completely by a threat of 1-2HKO, or revene killing, etc.
The only counters to Deoxys that I can think of are...
T-tar, assuming that deoxys is not Super-Powerversion.
Garchomp, as even the ice beam version is bleh
Strong Sucker punchers (I can't really think of many, but Absol might if it is correctly EVd, and has Choice band with a crit-hit)
Wobbuffet
So, my answer is a question of events.
Choice 1 - Wobbs/Chomp/Tar are banned.
Deoxys is UBER
Choice 2 - Wobbs/Chomp/Tar are not banned -
Deoxys is OU.
Choice 3 - The Latis are unbanned -
Deoxys is not uber.
Choice 3 leads to another question, but I believe that should be dealt with first - if we unban the Latis, is Deoxys counterable? The Latis would also create a new question - do we need to make a tier of BL-ubers, and what would the whole tier-system look like?
Plan of action proposed by me (feel free to ignore, but it is essential to my post)....
1.) Ban Deoxys and Wobbs, see if metagame returns to pree-Deoxys levels.
2a) If the metagame re-stabilizes, it shows Deoxys is Uber - skip to Step 5.
2b) The metagame is still horribly shifted to Garchomp/T-tar/Mence/Cressy, and allows them to sweep and centralize the metagame. Deoxys is not uber, and is re-introduced.
3) Introduce the Latis for a period of 3-6 months.
4) Determine the consequences of Lati participation.
5) If Lati intro overcentralises without Deoxys, re-introduce Deoxys for a period of 3-6 months to see if re-stabilisation occurs. If it deos, Latis are OU.
I hope you understand the post, and I'm sorry for going off topic. However, before tests are completed (which is never going to happen as the metagame is intended to be ever-changing), we cannot definitively say that Deoxys is uber.
Earlier in this post said:
So, my answer is a question of events.
Choice 1 - Wobbs/Chomp/Tar are banned. Deoxys is UBER
Choice 2 - Wobbs/Chomp/Tar are not banned - Deoxys is OU.
Choice 3 - The Latis are unbanned - Deoxys is not uber.
I put in alot of time and effort, do not look at this as spam or idiotic/moronic post.