Considering most new cars have A2DP bluetooth, this is less and less of a compelling feature--especially if it can't carry with it the ID3 tag info that some radios even support over A2DP. More importantly, it's so cheap to get a tiny FM transmitter that it's hardly a selling point. I picked one up a few years ago to use with my Palm Tungsten TX for listening to podcasts on the car radio.. it was under $10 and works with ANYTHING with a headphone jack.. even if I bought a new device. I began using it with my N800, until I started using bluetooth to listen to podcasts and then got a receiver for my car to also do bluetooth and I've avoided using FM ever since. FAR better quality and control with bluetooth in the car. Since the bluetooth adapter in the car is portable, I take it with my no matter the car, too--even works in my old '74 VW Beetle (AM-only radio... so FM transmitter wouldn't work there).

Just saying, at least in the US, FM transmitter is becoming the lower-quality alternative to bluetooth which is quickly becoming more ubiquitous in cars, headphones, speakers and other devices.