So, I'm leveling my death knight--currently planning to have her be a tank, but might do DPS; definitely going to do at least a bit of PVP in battlegrounds. As for professions, it's going to be Mining and something else.
I'm not asking you to tell me what to take, or even recommend which of the three complements to mining (engineering, blacksmithing, jewlecrafting) I should take--though advice on the pros and cons might be nice.
What I'm really interested in is--what does JC offer? Not just the actual items, per se, but... are those items likely to still be useful in the endgame, or will they be quickly replaced by heroic and early raid drops? What does it have that's truly unique, if anything, besides some BoP trinkets? And--how much money is there, traditionally, in cutting gems?
I know it's vague and can change with time and some of it remains to be seen, but... well, I've never done JCing at all before, so I'm at least curious to know what people who have experience with it think.