Im going to vote "not neccessarily" here.
Most of my riding is fairly short range around town, with frequent stops. The efficiency of clipless pedals will make hardly any difference to my speed.
For safety and security I use toeclips (in commuter mode, with the straps fairly lose). I find that they hold my feet in the correct position, allow me to hop curbs and potholes and stand safely on the pedals, but never hinder me from a quick dismount. Even when I am in the process of sliding on ice, I can can remove my feet instantly. They can be used with leisure cycling shoes, so the stiffness of shoes is not the big deal people make out, but I can also use them with any other shoes, including ones suitable for restaurants and pubs.
There is definately something to be said for improving on plain platform pedals, but the leap to clipless is not always the right one.
For those with longer commutes and simple A to B journeys, clipless may be a better solution, but not for me.