I will completely and utterly disagree. My player's wizard is a blood mage using staff of ruin, and some damage dealing dailies.
He does big damage on crits, and crits alot because he hits so many targets. His damage is often some of the highest in my group, especially if you add all of the multitarget damage.
I guess my main point was, wizards have to be specialized to compete. A high-con blood mage with staff mastery and some staff feats is going to be able to do some amazing things, of course. But that's a super-specialized type of wizard. But he'll be doing even better once the miss effect rules come into play.