The lag isn't really anythign to worry about.
It's the mirror that is slower, not the shutter. So, what causes and problems with the image, such as slight blurring is down to an overly eager photographer pressing the shutter and moving the camera rather than waiting a little.
I've no problems and shoot weddings with it.
As far as use doing weddings goes, it's certainly less of a distraction to the congregation and you can fire off more shots with it. But it doesn't allow you more freedom, walking up to a vicar and going 'look at my new camera, it's almost silent can I stand anywhere now?' won't afford you any extra leeway.