Computers & Video Games Magazine Online interviewed Shane Dabiri concerning the upcoming World of Warcraft: Burning Crusade expansion.  Although no further new details were revealed, there was a small bonus that clears up what Jewelcrafting Profession will be about:

CVG: What types of buffs/powers will jewels created in Jewelcrafting offer, and will powers from jewels put in sockets be on top of base buffs given by these items?

Shane Dabiri: We’re still examining how buffs offered by jewels will work with regard to those given by the socketed items themselves. Also, we’re not quite ready to get into the types of buffs that jewels will offer; however, it’s important to note that jewelcrafters will use jewels to create rings, trinkets, and necklaces, so you can begin to imagine some of the ways in which they’ll be very important to their fellow players.