When looking for a guild I want the app form to match the kinda progress and the overall seriousness of the guild. For a guild that raids a few times per week and is still in normals just do apps in game or have a short: Why do you want to join? Can you make the raids? Do you know how to play?
Higher tier guilds should have more indepth questions, Like ask for a screenshot and WoL (Anyone in a decent hc guild should be requiring logs, We almost instantly decline apps without logs) Talent choices, Gearing options ect
This is a also a very good question to have on your app:
Do you have mumble installed, working mic and are you able to attend our raid days at Wednesday 20-23 and Tuesday 19.30-22? Are you okay with having loot distributed with Loot council?
It gives the guy applying a lot of information. If he missed anything before applying it's good to tell him just general stuff even if it's written else were as well because having the guy show up day 1 but the week later he ragequits because of your loot system.