Mark - i have no idea about stats but the upload avatar feature does exist.
Im presuming it doesn't take up much space...
We actually used to have signatures
and people had like 3 huge photos at the end of each post.
This was disabled for band width and navigation reasons.
Are you thinking of adding an upload avatar feature?
Personally.. i don't really see the need. I mean this function that we have now, works although all the avatars are automatically resized to 100x100 which mucks up some photos but it's managable!