It's not the cheapest webcam on the market, but if you shop around you'll find it at a decent price. It genuinely is just plug and play with no software to install to set it up. Of course this also means that you don't get any fancy special effects either, so you can't add silly glasses or hats or backgrounds, but I'm sure I'll learn to live without.
What you do get is a very good quality HD webcam, the autofocus works as it should, the exposure copes extremely well with normal room lighting and the overall picture quality is excellent. The audio quality of the twin microphones is exceptional compared to the built in ones on your laptop (you can easily verify this for yourself by using the skype echo/sound test service). I'm convinced that the built in H.264 encoder does actually make a difference too, especially if you don't have the latest all singing and dancing fastest computer. It takes a lot of the load from the computers cpu. Most other HD webcams I've seen don't have this separate chip and rely on the computer itself to do all the processing.
It's useful that it has a separate removable usb cable. The supplied cable is reasonable quality (46" / 117cm length) but I needed one that was maybe a foot or so longer, no problem at all as I could just change it for a longer one. Most of the other cameras I've come across have a fixed cable.
Just one caveat... I've found it better to plug it directly onto a USB point on the computer itself rather than going through a separate USB hub. At first I was running it through the hub built in to my monitor and on a couple of occasions I lost connection with the microphones. It was dead easy to fix, just unplug and then re-plug the usb cable and all was well again. But I've since changed the connection from the hub to one on the computer and it's been fine ever since.