seta cl_demorecordmessage 0

It's something like.

cg_autoaction 3
Got the second one wrong

I'm not sure at all that either of those are right but they're in that vein.

cg_autoaction 3 for screenshot + demo
I recomend cl_demorecordmessage 2 (iirc it was 2) - it reduces the record message to a tiny little "REC" in the corner.
You could also check the god damn GUI.

For any further questions regarding console commands I direct you to this site:

http://www.regurge.at/ql/#comm

You can change it in the quakelive menus. No need for a cvar.

I thought you were going to ask if some pro is using it

cl_demorecordmessage 2 is the new adition I believe.

Instead of the full demo name being imprinted along the bottom; there is simply a Rec O (<--- big red dot) in the bottom left of your screen, nice and out of the way :)

For demo record and screen capture, I think it's cg_autoaction 3.

Srsly, for all the most recent cvar changes/additions; just take a quick browse through noctis's config every few months at www.ncts.at :P