Pugnacious Priest's Warcraft Blog

There enough tools at your disposal to do some basic investigation as to a players application for your guild. It really depends on how much detail and how serious a guild is in filtering their applications beyond an written app, a interview and a trial period.
One tool is Warcraft Realms. If anything it can give you specific questions you can ask someone. Eg You have been in 10 guilds since turning 70 – what were your reasons for leaving? An application may not list all the guilds they have been in, some guilds start and fall and disband, and rename ect ect so it shouldn’t be used as an indicator on its own as to a undesirable person for your guild… but it can be useful to find inconsistencies or give you questions to ask

All you need is the player name and realm.
Using Warcraft Realms It Gives you a complete guild history- with standard disclaimers as to the reliability of the armory..

Do a search on the character’s name, and it will give you a list of all realms that Name appears on.
Find the relevant realm, class and race and click on the toon.

My Profile shows
First Seen Dec 31, 06 ( When I hit level 9 for the 1st time)
Last Seen Aug 02, 08 ( most recent Armory refresh)

and then it gives you the guild history

70 P V Mar 03, 08
70 C D Jan 31, 08
70 Aof L Aug 06, 07
70 Unguilded Jul 20, 07
69 C M Jul 11, 07
68 C M Jul 04, 07
67 C M Jun 28, 07
66 C M May 31, 07
65 w and h Apr 30, 07
64 w and h Apr 24, 07
………..
15 w and h Jan 08, 07
15 Unguilded Jan 06, 07

What does that say about my toon?
I was in the same guild from level 15 – 65 – so a leveling guild
I didn’t raid before Burning crusade.. I wasn’t high enough
at 66 I left my home guild and stayed in one guild for just over a month
at 70 I was in a guild for 6 months
I left them for a guild I stayed with for over 1 month
and I’ve been in my current guild since March this year

Conclusions –
Ignoring pre 70 hence only looking at post BC raiding content.
I have been over 70 for a year, and have had time to have seen Kara, ZA, TK, SSC, BT Hjyal, and Sunwell. Doesn’t mean I actually have though .
I have a relative stable guild history in that I am not jumping guilds since 70 every month. I’ve been in 3 raiding guilds. ( a Wow Jutsu Search would tell you about individual progression for each of the guilds and hence give weight to some of my raiding experience as stated on application)
I left one guild after just over a month – and been in 2 guilds for a couple of months periods.
If those three guilds weren’t on my application as previous guilds I would ask why?

I recently looked up someone who had left our guild and had seen that over a short period of time he had guild hopped through all the top end raiding guilds on our server. He didn’t leave our guild on the best of terms, not sure as to the rest but to any future guilds he applies for , his instability shows that he doesnthave a good history of sticking around.. while maybe its not enough to reject him, its a point to consider, and weigh up with the rest of your assessment.

A tell tale sign that a toon is a server transfer is the lack of guild history on warcraft realms – that they suddenly appeared on the server at level 70
Its quite easy for a person with a bad reputation to change servers, and change their name, this makes it harder to track,  but a tool /armory crawler called Wow Progress have a detective feature that allow you to track server transfers and name changes. It only goes back to May 11th this year but its another place to look if things just don’t add up.

Another interesting feature in Warcraft Realms is that by clicking on the a guild name you can then track ex members, and see where they went. 
It also has other interesting things like tracking Battlegroup PVP stats BG Stats a census, Player, class activity…