Nice, I have been using the API a lot lately.
Just so people see what it says if they have not used the API yet.
The number 6503, is the number member you are. So mine said 6503 meaning I was the 6503rd member to join the site. Just for people who did not know.
And if yours is an animated .gif, you do not need to check, as it will be 20 by 20 every time.
Again if you did not see the original thread in the Announcements section, here is the API:
Original thread found here: New XboxMB API