Comment 8 for bug 77456

This is not a bug in Ubuntu, but a shortcoming of the linux-uvc driver. Many Linux applications access devices via the "read" method - the other alternative would be the "mmap" method. For example, luvcview can use either (the -g flag switches to the "read" method), Ekiga uses the "mmap" method, and Kopete uses the "read" method.

The linux-uvc driver currently only supports the "mmap" method. Applications that only use the "read" method will not work. Apparently supporting "read" isn't all that difficult, and it's a pretty big shortcoming, so I would expect it to be supported soon by linux-uvc.

To conclude, this isn't an Ubuntu bug, just a result of a missing (and very important) feature in the linux-uvc driver.