I'm writing this at 6am so that's why it's not beautifully structured, so please take your time and read all that's in here because it's all of value and it would mean an incredible lot to me if you listen to my ideas and take them seriously. Note though that it's more similar to Smogon's style of tiering than the 'budgetmons'-esque approach as was favoured in pokebattle before the in-progress rebuild.

Introduction to our main ORAS tier: http://www.pokemonperfect.com/forums/index.php?threads/introduction-to-pokemon-perfects-oras-1u-tier.3445/
Chat with Based Godfish - http://pastebin.com/KZxmmWNB - after he saw the above thread, I explain to him in greater detail the workings of the tier and the system and stuff.
Chat with Marty  - http://pastebin.com/1qKCrU6t - so basically this tier system has no way of really getting exposed and onto a decent sim if it's not on pokebattle (since PO's dieing and on the way out).

More stuff:
http://www.pokemonperfect.com/forums/index.php?threads/tiering-proposition.3438/ - Where our proposed method using viability rankings was suggested, has a good in-depth explanation of the process, though the introductino to oras 1u does a great job of it too.

http://www.pokemonperfect.com/forums/index.php?threads/is-it-time-to-move-on-from-usage-based-tiering.3343/ - Article openly discussing the possibility of moving on from usage-based tiering. Good read but fairly fundamental.

http://www.pokemonperfect.com/forums/index.php?threads/pps-tiering-philosophy.3417/ - Discussion of tiering philosophy

http://www.pokemonperfect.com/forums/index.php?forums/tiers.13/ - Subforum containing those previously mentioned threads, as well as other threads in some ways showing the tiering process in action. Everything above this though should be pretty sufficient to get a clear idea of how the tiering works, and there's definitely room for change and manouvring.

Note: PP is also the largest community for RBY more or less (pretty difficult to measure but we're on at least Smogon's level and have regular tournaments for it), and we have up to date resources, including analyses for ervery 1U mon other than dragonite currently (and we have a grammar/prose team).