Connecting adb over WiFi.
1) Connect your phone over USB.
2) Set the TCP port $ adb tcpip 5555.
3) Run
$ adb kill-server
$ adb connect 192.168.2.5
you will see
* daemon not running. starting it now on port 5037 *
* daemon started successfully *
connected to 192.168.2.5:5555
Recording video
4) While in a shell, the syntax is screenrecord [options] <filename>.
To use screenrecord from the command line, type the following: $ adb shell screenrecord /sdcard/demo.mp4
5) (press Ctrl-C to stop)
More info on bitrate settings and stuff here : http://developer.android.com/tools/help/shell.html#screenrecord