well im a newbie and everything in the first page helped me. first you have to get the tools:

open xterminal

type:
apt-get install gstreamer-tools

after that type:

gst-launch v4l2src device=/dev/video1 ! autovideosink

it will pause for a min then it will come on.

hopefully soon we can get a real webcam app that can initiate the front cam instead of all these damn work arounds. lol would be nice to have one with cam settings like resolution and brightness.

hope i helped. this is what worked for me