Need help with a MySQL query

gistfile1.txt

I have the following query:

SELECT brand.id, u.created_at 
FROM brand
LEFT JOIN brand_admin_group bag ON brand.id = bag.brand_id
LEFT JOIN brand_admin_group_membership bagm ON bag.id = bagm.brand_admin_group_id
LEFT JOIN user u ON bagm.user_id = u.id
GROUP BY brand.id, u.created_at

Results look like this:

23,"2011-01-04 16:55:51"
24,"2011-01-04 17:19:46"
25,"0000-00-00 00:00:00"
26,"2011-01-08 17:25:18"
27,"2011-01-08 22:34:55"
28,"2011-01-10 07:33:59"
29,"2011-01-12 08:06:30"
30,"2011-01-12 08:54:09"
31,"2011-01-12 09:12:20"
32,"2011-01-12 09:18:42"
33,"2011-01-12 09:19:58"
34,"2011-01-12 09:20:15"

Now, what I need to do is come up with a query that counts the number of brands grouped by the month of creation. u.created_at is a datetime field (ie 2011-02-08 19:13:58).

Any help would be appreciated