I noticed it this morning. I don't need an authenticator to log into WoW, but I do need it to log in to Battle.net. I opened a ticket a few hours ago, before I read this thread. I thought it was a weird bug with WoW and was afraid of getting hacked.
Mentalfrog wrote:
I wouldn't mind not putting it in all the time for things like DCs but I would still rather put in a number on a daily basis at least for the first login. If anything it lets me know the thing is still working.
I'm in agreement with this. My account was hacked and all my gold/items stolen over a year ago; it was like a punch to the gut out of nowhere. That was what prompted me to get an authenticator. I've grown a bit paranoid about account security since then.