Hi Bob,
While I was writing about charcoal grilling, my Genesis gas grill didn't get much use at all. I kept many of tools under its lid but didn't fire it up for months. Lately I've been cooking with my Genesis, however it doesn't have an infrared burner. My experience with infrered is pretty much limited to some rotisseries I used in cooking school. There I noticed that infrared can caramelize (brown) the surface of food much faster than an ordinary gas or charcoal flame can. That's great, but I've never had trouble caramelize food the old-fashioned way. I am not sure what Weber has planned for infrared in the future. I'd be surprised by a combination of charcoal and infrared.
All best,
Jamie