You can now upload your own Avatar through your profile.
Click on your Profile tab
On the left menu click on Forum Profile
Then click on Upload an Avatar
Browse to your computer to upload an Avatar.
TIP: Try to keep the image size below 160 by 160 because the forum will resize it to that anyway, but if you upload larger images it will slow down your posts appearing.

Example: a 1024 pixel image will still load at that size but will only be displayed at 160 pixels