I finally convinced a couple of enthusiastic Arena newbies from my guild to do a few games and managed to get myself a new tabard.
It's not really the prettiest-looking tabard (and totally doesn't go with the murloc armour), but I'm definitely keeping this one.
I'm also hoping to continue the 2v2 or 3v3 games - surprisingly our hunter/warrior/mage combo didn't completely fail, even with the warrior not having done Arena and the mage not having done any since lvl 70 on a different class.
Not to mention, it's been a long time since I've been in a triple-DPS team and it's hard for me to call shots in a faster-paced DPS-only match when I haven't even had much practice in the current Arena environment (when did they get rid of the Ring of Valor starting elevator?! I approve! :D).
I don't know if I'll ever make Challenger again, but hey, one can only hope! :)