As far as I know, it takes a standard action to activate the Fleeting Glance power. However, since the recent update Hero Lab insists that it's a swift action and I can't find anything in the rules that agrees with this. Is Hero Lab being odd or did I miss some errata?
By my guess it originated as a copy of the Illusion wizard school's invisibility power. It's identical to Fleeting Glance with the exception that the wizard power is a swift action and the fey sorcerer one is not.
Not to dig up an old thread, but is this true? I guess I originally thought that it was intended to be the same as the illusion wizard's power. Needing a standard action to activate sorta makes this power suck, since at that point you're wasting an action on something that you could have just cast anyway and would last just as long.