Shoot manual, and adjust as you go.
For all the tips, and tricks people will give you, you're going to find a sweet spot with every shot you take, if your camera is underexposing, then pull back your shutter, if it's over exposing but your shutters already quite high, dial back your aperture.
And if the venue sucks, wait for more light, or just shoot and worry about it later. These days atleast we have post, also with concert stuff, I don't recommend shooting raw unless you plan to A blow it up, B there's a lot of blow out, Concert is fast paced, you chew through memory cards like there's no tomorrow and the noise gained from shooting Raw isn't worth it, it's easier to gain crisp shots with minimal editing (especially if you have to have my turn around times, which are usually 12-24 hours)/
I "prime"arily use 24 L II, 50 1.4, 85 1.2, and 1.8, (I favour the 1.8, because it's light and practical, the 1.2 is for crazy shots, where I know I'm in a cave pretty much, and the 1.8 is more practical) and then the I have the 70-200mm when I'm asked to do something crazy like Kanye West (that was insane, I sat at 800iso at f/4 at 1/200 and still managed to get way too much blow out in a lot of the shots).
I don't recommend the 24-70, or any other zoom. Too many idiots with not enough light coming through there lens these days favour that, and get frustrated when I can get the shot and they can't
Also if the lights F_____ go for close ups, you'll get more accurate focus and if you have IS, you'll get a lot out of that feature then and there. (Probably the only time it's useful).
http://ofoliver.tumblr.com for some idea of my concert work (to know I'm not just giving my 2 cents for the sake of it), I prefer the challenge of shooting stuff that's hard, and at the moment I'm favouring smaller stuff because you get more time to get your shot (when I've shot stuff like Foster The People, Two Door Cinema Club, Jimmy Eat World etc etc, it's 10 minutes or less, often 3 minutes ~ Gotye I got 45 seconds, because the PR girl in charge was a drunk mess but that's another story).
Don't use flash unless there's people moshing, and don't discount the atmosphere around you, those can help you build up to your leading shots, and try not to use the same shots in your gallery/portfolio over and over again. I like to really take my time, I make sure I get the perfect shot with my tele, then I might move around stage, what for the star to move or switch to the 24mm, or the 50mm, to get a different effect more light, crowd shots or whatever, the same shot can be boring. That even applies during if I've only got 10 minutes.
And make friends with security when you can, they will let you do some dodgy stuff like jumping over barriers, or climbing side stage, or going up into the DJ booth when you really shouldn't. Those can help you get the best shots, (I did that with the Wombats most recently, went back stage, and snapped a few looking out over the crowd).
And 2.2 isn't high if the lights good, no one knows what the venues like except you, so shoot prime, shoot fast glass, and crop/full frame really isn't that important (I carry both a 7D and a 5D for concert work).
i really like the composition (except for a photographer who was alowed in the pit has his arm in the bottom left corner). For this I think i just got the focus and took the show straight away. The focus in DPP says i got her cheek, but its the microphone cable thats in focus! 
I really love mine, got some awesome shots from a show, it was like a dream. Especially the AF & ISO noise!
