It doesn't appear to be a cell phone jammer, just wifi and Bluetooth. So they'll still be able to talk on the phone, just not using the "look how important I am" earpiece.

Unlike cell signals, wifi (and I'm guessing, Bluetooth) operate on an unregulated frequency (I believe the same frequency as your microwave and home wireless phone), so I'd guess these aren't illegal. The thing that makes cell jammers illegal is broadcasting on a regulated frequency. On the other hand, trying to take one on a plane, I'm not sure authorities will be interested in the distinction.