Yah, they did a crappy job "announcing" this. I don't have it handy, but one of the executives made a vaguely-written Google+ post, with a reference to Google "expanding" the numbers you could call, and mentioned that there may be a charge, but there is no way to pro-actively looking up a number to see if it will be charged or not. I guess, for $.01/minute, it isn't worth writing the code.
Anyhow, now you know.