We did have a Portfolio Page before we had a new vbulletin skin, but this new vbulletin skin doesn't compact with the Portfolio Page so we had to get rid of it kinda. I think if Horia said rightly, if we had a Portfolio sub-forum it may take too much room on the board which would lower the Site performance. As we have new areas of SA open, such as the Sig & Render Galleries. I am unsure as we have't talked about this for a while but i'll talk to Horia (Nico21Horia) again about it, as I agree it would be ideal to have one again. If not, for a short time set up a DeviantArt Account or something.
See we have a Page full of Portfolios here, but people can't make new ones so it defeats the point of it really.
http://www.soccer-art.co.uk/forums/vbgarage.php?
Hope that helps