Okay, I just ordered a Flip Ultra HD with a spare battery pack (free!).
I decided to go with the Flip for a few reasons. After I discovered it had a real tripod mount and could be mounted like any other camera, I took it a bit more seriously. So the main decision became: do I get a toy camera, or a higher-end one? I do like the extra abilities of the real cameras, especially the image stabilization. The Hero is simply not in the running, as I got burned too hard on the previous version. It might be awesome, but it's going to be someone else's awesome. I have trouble taking the engineering seriously with such a retarded interface.
Looking at image stabilization, it appears the Canon I'd been drawn to has some weak points. But there's a Panasonic with stabilization that's so good it's freaky - there's a Youtube video that compares them both in the same car side by side. So it was Panasonic HDC-SD20 vs Flip. In-car video shows the Flip does suffer from a lack of stabilization, but with a good mount this is kept to a minimum.
The fixed focal length of the Flip was a bit long for me - I like a fairly wide angle for in-car. Then I discovered that a lot of people attach threaded rings to the face of the Flip and attach an inexpensive lens to that. Videos show this to be fairly effective. Okay, there's an option.
But the kicker was when I thought about what bothered me with the current DV setup, and the biggest problem (besides the fact that the camera fell apart) was the effort in getting the video off the tape on to the camera. I liken it to shooting photos on film, developing them, scanning them and then manipulating them. The Flip is just so easy to use, and the Panasonic uses a fairly high-end format that would have me playing the conversion dance. That sealed it. I'm going to try the Flip and see how it does. If I go back to the Targa, I might do something else. But for track day goofing around and general having fun, I'm going to go for convenience over ultimate quality.
After all, the best camera in the world is useless if you don't use it.
I'll follow up after a couple of track days - I have four days planned in the next three weeks, including a long weekend at Laguna. Should be a good test.