Ok, here's my take on consumer camcorders. I am a professional videographer/photographer and when I looked over at the consumer side for my handheld HD Camcorder I narrowed it down to two. The Canon HV20 (mini DV) and the Panasonic HDC-SD1 (High Capacity SD Card), and that was after hours and hours of searching and comparing the video in Final Cut Pro. I bought them both because that's how I do things I guess.
Both shoot excellent video, but I chose the Panasonic in the end because I absolutely hate dealing with tape. The AVCHD codec is amazing, though a bit ahead of its time perhaps. I don't know how to capture video on the PEE CEE side, but with a Mac I just capture it using Apple's PRORES 422 codec and it looks simply amazing. It outperforms the Canon in low light situations, which is often the case when shooting home movie junk. The Canon did have a slightly better picture in full light, but I really can't stand tape. You will need a whole lot of storage for the Panasonic, but again, for me that's no problem with a 20 Terabyte machine at work and a 6 Terabyte machine at home.
The Panasonic is a lot cheaper too, and you can get 42 minutes of the highest quality video on a 4 Gig chip, which are pretty cheap. Those cameras, in my opinion, are the two strongest. JVC makes cool stuff, and I did an entire training video on their Everio line, but it's their own proprietary codec and that's when you start going down the Sony path, which always leads to more money and disappointment (I absolutely loath Sony).
That's my opinion. Might as well go High Def if you are going to spend the money. If you don't you will regret it in 5 years when you look back at that old looking crappy 4:3 480i picture. Good Luck!