A few questions about guild perks...

[Kalico]

Used the search function to see if someone had asked this... but I didn't stumble into the same question. My apologies if someone has asked already :<

To my understanding, guilds will be leveling from doing various things (from pve, to pvp, raids, dungeons, etc). Does anyone know how exactly this will go once Cata drops? IE. Will every guild start from 0 regardless of their time created, or will older guilds have an advantage? Will you need a minimum number of individuals with X achievement in order for the guild to get credit for it?

[Matchu]

Presumably, for achievements like "collect 10000 fish", you'll have to go collect that amount from Cata. Same for "Do X dungeon in a guild group". The only ones that might tick over instantly are "collect these legendaries" but since I think the achievement also includes the Cata one, it'll be impossible.

[Emaluri]

All guilds start at level 1, 0 XP. The guild itself earns the achievements, so they have to be done after the leveling system is implemented.

All guilds will be on perfectly equal footing, to start. Depending on the number of members and their various activity levels, some guilds will progress slightly faster than others. Guild XP will be somewhat gated, so larger guilds won't progress in level drastically faster than smaller guilds, even though they'll still have the advantage when it comes to some achievements (10,000 fish, for example)

[eternalwhitemoon]

I'm not sure about the experience (I would assume every guild would start clean) but here's the numbers for what counts as "guild":
"In general we require 80% of the group to be comprised of guild members. There are exceptions to this case though like 40 man raids and arenas. All the gritty details below are below.

4/5 - dungeons
8/10 - 10 player raid, 10 player BG
20/25 - 25 player raid, 25 player BG
10/40 - 40 player raid
12/15 - 15 player BG
2/2, 3/3, 5/5 - Arenas"
-Mumper

Source: http://blue.mmo-champion.com/t/26560...ungeons-raids/