The first time I requested a name it took 3 days for it to get approved. The strange thing is, it's hard to tell if it rejected the name right off the bat as being taken. If you enter it twice it always seems to come back and tell you to choose another. I've entered names that couldn't possibly be taken (you'd think) yet the system claims it is taken. I think the process of requesting a guild name definitely needs improvement.
A great idea IMO would be for the existing names to pop up in alphabetical order (in the game) so you can see what is already taken.

irate3: