I saw an interesting thing on a TV show I was watching the other day. A character's iPhone "rang", while on vibrate. I recognized the distinctive iPhone vibrate sound right away. Think about that - the purpose of the vibrate feature is to silence your phone to only alert the owner to an incoming call, yet the sound is audible and distinctive enough that it can be used in a TV show to convey an incoming call without using the Marimba sound like the show Phych goes for. So, when I saw Apple was doing this, I applauded loudly... on vibrate.