Up to 2GB internal memory: does that mean internal SD slot is now "hardwired" to two GB non-removable, or that a non-SDHC card is used?

400/330 Mhz difference isn't much, and the rest of the "internal" specs are pretty much the same. We'll have to see if they did anything to the video, but I'm guessing no guarantees.
The hardware similarity leads to the expectation that their software improvements (mozilla-based browser, video talk client that works, improved media player).

The car charger and mount means they can try to sell this through GPS/SatNav retail channels. Come to think of it, that would at least get them someone who would sell it in the stores.