Gmail Telephony: Your Call May Be Recorded

"Gmail recently added the ability to make phone calls from your inbox, and they've recently (silently) rolled out the ability to record incoming calls as well."

The ability to record incoming calls using Gmail is a useful feature, but is it legal without a disclaimer stating that the call may be (or is being) recorded? One of the subsequent comments was interesting, in that they stated that all calls are recorded, this just gives the end user access to the recording. This would make sense, as VoIP calls are really just a low-bandwidth data stream.*