May be this is late reply and you have already made choice, If so, please post your choice here; otherwise here it goes.
I am also on the hunt for good handycam and I am seriously looking at these HDD based handycams. What I have read so far, I wouldn't buy these handycams for still pictures as almost every knowledgeable individual points at bad image quality. Ultimately, this is video camera and expecting good stills capability may be too much to ask for at this point or from the company's point of view, may not be good for their profitability.
Yet, few reviews did mention about above average low-light performace which you would look for if you are more going to shoot indoors and that too without much of flashy lights (in early days of little kid)
GZ-70 is top line of the products, but if you ignore still capability then even GZ-50 should suffice your purpose, it also has F1.2 bright lens (I am yet to figure out what exactly it is) and buy nice 5MP canon IXUS 50/55 for stills!!
Baby on the way, so I'm looking for my first camcorder. Love the idea of the Hard Drive system. I realize I'm not buying a camcorder for the still picture ability, but what is the difference between the JVC GZ-MG40 vs. JVC GZ-MG70?
Or should I wait for the JVC GZ-MG77 or Sony's DCR-SR100 reviews to come out?!?!?
When will CNET get there hands on these new cameras to do a "FULL" review on there video capabilities? Thus, far I haven't read anything too great about the picture quality of the MG-70.

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