Hei Alex,
I am not sure what they wait for but probably they ask our countries for a Certificate of good conduct, and thats why it takes long. I really have no idea why they take all this time to review and process a paper.
A month is like 20 working days only they do not count the weekends at all. Some people get their visas before the expiry date by 4 days only while other lucky ones get it in 3 days or a week max.
Lets hope this week we get it.