Yeah, it's pretty crazy. These days every house has a radio, multiple cell phones, tablets, wireless internet and god knows what other kinds of wireless devices. I'm betting that in my street alone we'd easily have over 200 wireless devices already, and that'd probably be a conservative number. Add to that all the radio traffic, cell phone traffic, etc. and you get quite a busy sky.
It's actually so bad that on my telephone (VoiP) I hear a radiostation of some sort when I pick up the receiver, and I have absolutely no idea where that sound comes from. At least it doesn't sound very loud, or it'd interfere with my phonecalls, but it's still weird to have that happen.