Late last season, the YouTube channel Copa90 visited Seattle and put together a pretty awesome documentary about the fan culture here (video above). Even if yours truly wasn't one of the featured interviews, I'd still be proclaiming its awesomeness. Well, they are getting ready for a sequel of sorts.
Copa90's producers are back in the Pacific Northwest talking to folks from the Seattle Sounders and Portland Timbers about their rivalry. It's part of the series titled "Derby Days." My sense is that this one may focus a bit more on the Timbers and Timbers Army, being as it was only about six months ago that they did that other feature, but given their track record I suspect it will be very good.
For those of you who might not be familiar, Copa90 goes around the world doing features that are mostly focused on soccer fans and fan culture. They've put together some really great stuff.
Also, it appears they are at least interviewing some people from the Sounders side of the rivalry, so it shouldn't be completely one sided.