The question in my mind is whether these items will remain available post-expansion. My bet would be that they'll vanish, and this will just have been a fun little jewelcrafting preview. As far as I know, no significant crafted items are currently available from vendors, but maybe that's set to change.
Additionally, new and more powerful water, food, arrows, and bullets can be bought from an orc vendor named Galgrom deep in the Caverns of Time in Tanaris. The arrows and bullets are also available from general goods vendors throughout Azeroth, and seem to be a much better deal than the water, which as far as I can tell is exclusive to Galgrom. At over 10s for one drink, I probably won't be buying the water for general use, at least not until after I get my epic mount; the ammo costs 10s for a whole stack.
Have you all spotted any other BC items that have snuck in with the patch? And those of you who have tried the Filtered Draenic Water, how would you rate it? Does it make financial sense for someone with a mana pool around 6k?