I believe exposure is giving away a secret to a trick in a public venue, to someone who did not request the information or does not plan to preform the effect. If you are explaining a trick to someone other than a magician in private you are probably exposing.
Penn & Teller - EXPOSURE
While they have an entertaining show, they are still teaching secrets in public to mainly non-magicians, who have no intentions of preforming the trick.
Brad Christanson's Ninja Gambling Routine - EXPOSURE
A great performance piece, but you are still exposing the pass to people who never plan on doing it.
Open Travelers/ Invisible Palm - EXPOSURE
This was border line for me, but if you show palming then I would classify it as exposure.
VAL VALENTINO - BLATANT EXPOSURE
Just know if I was on the jury, you wouldn't be convicted .... all I am saying.
I think it's okay to teach other magicians for free in private, and not be classified as exposure. Most tricks are not new, and usually just a tweaked handling of an old effect. We all know magic has crediting issues, and most people are not doing anything new.
If you created an effect are you fear it being exposed, then don't market the effect. Plain and simple.
What do I do to combat exposure? Well I don't call effects by their real name. This prevents people from googling by tricks.
I like to look for effects in books, because well most people aren't exposing them on you tube.