Video of TomTom's iPhone accessory and app

We saw photos of the TomTom accessory for the iPhone yesterday but now we have video of it. This is basically a little dock with a USB cable and a GPS booster. Not a huge deal but this could feasibly mean the end of standalone GPS devices, which is kind of important. What think you?

Would you replace a standalone GPS device with something like this? Do you already use something like this – maybe a BB or a WinMo phone tethered to the dashboard?