All right, I'm seeing a lot of things that should be addressed that haven't been answered to until now. Since voting has already started and a good amount of people have voted some opinions can be changed and those who are undecided can make their decisions before they make their vote. If you have already voted and your opinions change from this post, you can still change your vote by talking to the council members about that.
I've already spoken up about Aegislash in this thread and on PS about my stance on the matter. One thing that I see a lot of people clinging to is this fallacy that Mega Heracross, Mega Medicham and Mega Gardevoir will be become so rampant that Offense will dominate the meta and stall/balance won't exist. I can tell you right now this is false for a couple of different reasons. All three of those have more issues to deal with than just Aegislash before they become the "terrors" many of the anti-ban think they will. While all three have great wallbreaking power, in a metagame where offense is dominant, the only one that will potentially dominate is Gardevoir. Mega Medicham is really frail and while it can theoretically beat most Pokemon on offense, what can it switch into? Not only that but most offensive teams have no issues OHKOing it. Mega heracross can come in get a kill then what? With such low speed it's really easy to revenge or force out and against most offensive teams, it's probably not getting another chance to come back in. Trying to justify Aegislash as a means to keeping them down especially when they have been on the rise in a metagame with Aegislash anyway (look at viabiltiy rankings/WCOP games and see how common they are becoming with Aegislash in the meta) is not only a baseless assumption but also false.
People also said that once Aegislash leaves, stall becomes nonexistent because it can't handle all of three of those threats. Did people forget that stall already has a hard time trying to deal with those? Aegislash isn't even used on stall you "counter" them. The only known Aegislash stall team out is was
KratosMana's team in his match with dragonuser. That's really the only one. Like CBB said if Heracross, Medicham and Gardevoir really want to get past it, they will. I'm sure someone will say that the suspect ladder was filled with offense and stall was nonexistent. First off, every suspect ladder is like that. People will always use an "easy mode" ladder team to get through it as quickly as possible. So on suspect ladders you will almost always run into HO/Offense and this shouldn't be indicative of what the future meta will look like. In that same vein, there were several stall teams on the ladder that were actually good and were plenty viable.
A lot of people have mentioned that we're trying to build XY into a more desirable metagame. If you haven't read
DougJustDoug's post on what a desirable meta should be like, please do, it should give a good idea of what we're aiming for. While people may say that the current XY OU is a fairly desirable metagame, I disagree. Why? If you really look at OU in the last few months (start of WCOP to now), how truly development have we really had? Very little. The last noticeable "shift" you could point to was when Ttar / Exca / Mola became a thing, ever since then nothing has really developed, the meta has just kinda stalled. If you take a look at WCOP replays, it's become more and more apparent that teambuilding is tightening. Teams are becoming more and more similar to each. This isn't a good. In fact, we are beginning to fall into the cycle of BW2, where you basically only play a handful of playstyles and teambuilding is so restricted that every team looks like a variation of someone else's team. You don't believe me? Go take a look at
WCOP replays, look at the BW2 games and tell me how much diversity there truly is. Very little. Aegislash can be compared to Rain in BW2; a huge presence that seemingly keeps the tier in a "balance" and made it "more diverse." Keeping Aegislash in the tier won't improve the tier it will only make things worse 2-3 months from now. Teambuilding will become more restricted and the tier will become less diverse.
My point here is while people can say things like "it's not hard to beat", "it's weak to several common types in OU" (which Gr8astard already proved to be false), it still doesn't deny Aegislash's effect on the tier, the ability to force 50/50s, it's "easy mode teambuilding" (similar to Genesect). All of these are adverse and unhealthy effects on the meta. I truly don't think XY OU will ever progress the way it needs to as long as Aegislash is in the tier. It prevents development and affects further suspect testing because Aegislash will always mask the issues that the tier has. There is much more to gain by banning Aegislash then there is by keeping it. What is there to truly gain by keeping Aegislash in the tier? Status quo? Stability? But is all that really worth it? Do people want to fall in the same cycle that BW2 fell into? If not, please vote ban Aegislash. If you want an un-evolving tier with stifled teambuilding vote do not ban. I can't force you to vote a certain way, I can only try to change your mind.
tl;dr: Read the post...