Yes, you can edit and post 30-second clips to youtube... and then to the Base Theater... and here's how...
1) Go to
http://www.callofduty.com/blackops and register
2) Go to "Theater" on the website and link your CoD account to your Youtube account so all uploaded videos go there...
3) Launch CoD and play a clip from your recent games or file share
4) Find a segment you would like to capture, and select the RECORD option.
5) Once you have reached the end of your segment, select RECORD again to stop.
NOTE: Segments can be no longer than 30 seconds.
6) Select NAME SEGMENT > UPLOAD CLIP, then create the TITLE, DESCRIPTION, and TAG for the video clip
7) Select a slot in MY FILE SHARE to save the video clip.
8 ) Go to MY FILE SHARE and select the video clip.
9) Choose the SELECT FOR PLAYBACK option. That video clip will now be available to render.
10) From the Call of Duty: Black Ops THEATER (in-game), select RENDER CLIP.
11) Watch the video clip in My Theater (online or in-game) or on YouTube.
12) To post videos here, put the link to the youtube page inside youtube brackets