Remember a few weeks ago when it was discovered that the Armory was listing the new Badge of Justice-reward epic gems at 10 badges each? Yeah, turns out that was just an Armory bug (which we knew was a possibility). They're 15 Badges after all, as they were on the PTR. The way we know this now is that Proudmoore-US, first in all things Shattered Sun, has done Discovering Your Roots enough times to unlock Shaani, the vendor who sells you the gems. Thanks, Proudmoore! Grinding for knowledge. And everyone else, get on that quest. It's a fun one -- everyone gets a pet so they can pretend they're a hunter for a little while -- and you'll help your server along.
Assuming the epic gems sell for around 500 gold, which seems reasonable given the order-of-magnitude increase in price between uncommon and rare gems, this yields a 33 gold per Badge conversion rate (if you buy gems with your Badges and sell the gems; they're not bind-on-pickup). That's right on target in terms of gold per hour. I figure it takes about 20 minutes on average to earn a Badge, which means 100 gold per hour -- pretty much the same rate I make through dailies or grinding. And given that any activity that earns you Badges (i.e. raiding or heroics) gives you a chance at gear as well, it looks like the PvE endgame is fairly rewarding right now.