The deadline to submit requests was supposed to be this week but it's been extended until November 5th.
So if you ever had a plot bunny that you wished someone would write for you, an icon that you really wanted, a new header for you LJ ... this is the place to go! There are no guarantees that it will be granted but there's no harm in trying right?
Go check it out. Maybe you can ever fulfill a request for someone else! I don't think there's any deadline for that. :)