Until now. A fellow Shaman friend was running the Mana Tombs, and announced in guild chat that he'd grabbed the Lightning Rod Pauldrons, a terrific set of mail shoulders that drops from Tavarok in there. I drooled over the stats, and then CTRL-clicked to check out how they'd look on my Shammy, and lo and behold, I'd found my shoulders again! The devs had reused the Tier 0 skin, in new and cooler colors! Now I've got a new goal to run an instance over and over again for.
And a lot of people are living the same dream. Cearrdorn over on LJ really likes the Judgement set, but his guild never made it long enough in BWL for him to get the whole thing. Fortunately, it looks like almost the whole set is findable in different colors in Outland, most of it in 5-man (both regular and Heroic mode) instances. I can't wait to find a Bloodfang lookalike for my Rogue, too-- for those of us who were never able to get all the cool-looking high end gear we always wanted (for whatever reason), it looks like the devs, by laziness or design, are giving us a second chance by reusing the old skins.