One of the (few, but legitimate) reasons given by some Windows users to not switch to Linux is that many pieces of hardware are not recognized by the latter. Sure enough, 99.9%, if not all, of the devices sold in shops are "Windows compatible". The manufacturers of devices make damn sure their device, be it a pendrive or a printer, a computer screen or a keyboard, will work on any PC running Windows. They will even ship a CD with the drivers in the same package, so that installation of the device is as smooth as possible in Microsoft's platform. Linux compatibility? Well, they usually just don't care. Those hackers will make it work anyway, so why bother? And their market share is too small to take them into account.
Now, let's pass to some personal experience with a webcam. I bought a webcam for my girlfriend's laptop, which doesn't have one integrated. The webcam was a cheap Logitech USB one, with "Designed for Skype" and "Windows compatible" written all around on the box. It even came with a CD, marked prominently as "Windows drivers". My girlfriend's laptop runs Windows Vista, and I decided to give it a chance, and plugged the webcam without further consideration. A message from our beloved OS informed me that a new device had been plugged (brilliant!) but Windows lacked the necessary drivers to make it work (bummer!). OK, no problem. We had the drivers, right? I unplugged the camera, inserted the CD, and followed the instructions to get the drivers installed. Everything went fine, except that the progress bar with the installation percent went on for more than 12 minutes (checked on the watch) before reaching 100%. After installation, Windows informed me that a system reboot was necessary, and so I did. After reboot, the camera would work.
As I had my Asus Eee at hand, I decided to try the webcam on it. I plugged it, and nothing happened. I just saw the green light on the camera turn on. Well, maybe it worked... I opened Cheese, a Linux program to show the output of webcams. I was a bit wary, because the Eee has an integrated webcam, so maybe there would be some interference or something. Not so. Cheese showed me immediately the output of the webcam I had just plugged, and offered me a menu with two entries (USB webcam and integrated one), so I could choose. That's it. No CD with drivers, no 12-minute installation, no reboot, no nothing. Just plug and play.
Perhaps it is worth mentioning that the next time I tried to use the webcam on the Vista laptop, it would ask me for driver installation again! I don't know why... I must have done something wrong in the first installation... With Windows, who knows?