Just some useful commands:

• Make sure your RPI is up to date:

sudo apt-get install rpi-update
sudo rpi-update
sudo apt-get update
sudo apt-get upgrade

• Check capabilities:

vcgencmd codec_enabled MPG2
vcgencmd codec_enabled WVC1

vcgencmd version

Jun 17 2015 13:36:16
Copyright (c) 2012 Broadcom
version 1352d17ed6bd078120ac262b8c45b5b3a0d398de (clean) (release)

• Streaming of USB video camera:

Start streaming on Pi:

cvlc v4l2:///dev/video0 --v4l2-width 640 --v4l2-height 480 --v4l2-chroma h264 --sout '#standard{access=http,mux=ts,dst=0.0.0.0:8080}

Start watching on client:

cvlc http://10.6.23.101:8080

Bonus, autostart streaming at boot:

Add streaming line to script
sudo chmod +x /home/pi/bin/stream.sh
crontab -e
@reboot /home/pi/bin/stream.sh

• Configure WLAN

sudo vim /etc/network/interfaces
allow-hotplug wlan0
iface wlan0 inet dhcp
wpa-ssid "YOUR NETWORK SSID"
wpa-psk "WIFI PASSWORD"
sudo reboot

Or install wicd-curses and wicd-daemon