Blizzard really does seem to have finally realized that can give us a few more decent ways to save space without breaking anything or trivializing the game. The new vanity pet and mount skill system has done wonders to clear up bag space on my characters on Beta, and I just can't wait to be able to do it on live.
Of course, there's tons more stuff that a good, solid pack rat can keep in their bank to take up space, from cool looking quest rewards to old gear sets to tabards. Tabards are an especially massive space investment. Even with just the basic battleground and unique event tabards, we're talking at least half a good bag taken up in the bank, and that's with deleting all the easily re-obtainable tabards to save space.
To some extent, Blizzard seems to have realized this, making unique tabards recoverable along with pets and keys, but it would be nice if they could take it one step further and put Tabards on the same skill-type system as pets and mounts.
Because of the new championing system, switching up tabards will probably be a pretty regular occurrence. Buying and rebuying tabards and heading back to the bank to put your unique tabard in storage for faction grinding will end up being a regular chore, and it seems likely that we'll be changing up our tabards often. Having a "Tabard skill" system would enable us to decide which group to fight for on the fly without having to fly out and buy or rebuy their tabard just for a bit of rep grinding. In addition, it would allow us to continue to fly our guild or battleground or faction colors with pride during downtime with a minimum of fuss.
Given the fact that tabards are becoming a central game mechanic in Wrath, they deserve to be easier and more convenient to use and swap so that they can also remain a valid way to make a fashion or loyalty statement when you aren't grinding. Here's hoping Blizzard's realized that, and has one more nice little space saving change up their sleeve.