Other reviews have fairly described the pros and cons of the TG1. I own a Canon HV20 for "tripod events" - nothing beats HDV for image quality and low-light performance, and I always use a quality Senneheiser wireless mike for subjects greater than 10 feet away. But there are too many moments in life - of one's kids, mostly - that are over by the time you go get the beast, make sure there's room on the tape and juice in the battery. These are what the TG1 was designed for - it's your second camera, for the moments that normally get away.
I think the design and execution of the TG1 are brilliant. The IS and face detection work very well. Yes, I would have loved a mike input and an exposure button. But my guess is that Sony made these decisions of omission very carefully. If you have been waiting for a decent-quality shirt-pocket HD camcorder - as I have been ever since flash-memory models hit the market - didn't you expect to pay four figures for the early-adopters' privilege? Just think about it - this machine is roughly 30% smaller than its nearest competition, and Sony brought the price point for such exquisite miniaturization down to a level competitive with the other premium flash-memory camcorders. Every extra button or dial would have driven up the price of the unit. Design simplicity may have been a motivator as well - the camera's native point-and-shoot capability is just fine for about 75% of the moments most of us are trying to capture, and more buttons would make the unit a bit more geeky.
BTW, I have not had any trouble importing and manipulating AVCHD on my Lenovo T61 Thinkpad. The video editor is certainly meager - one can divide and trim the videos, and that's about it. But the DVD-AVCHD burning utility is fantastic. I had about twenty minutes of video from my first week with the camera. It took about 15 minutes to burn them onto a 25-cent DVD-R, and watch it on my Blu-Ray player (BDP-S350), and the daylight images were beautiful and sharp, even on a big screen.
From shooting my kids for the past week indoors and out, I have one other thought about the TG1's low-light drawbacks - they are more than outweighed by what I call 'form-factor-comfort'. It's not just the delay in getting out my big HDV unit that lets those little moments get away - the size of the tape units is inherently conspicuous and inhibiting, and my kids become self-conscious. The TG1 is roughly the size of my iPod, and its small size makes it much less intrusive in real-time. The little goofy moments when my 15, 13, and 8 year old kids all act like they're three years old are not perturbed by the TG1. This kid-comfort factor is of inestimable importance, in my opinion.
There might be two diametrically opposite subsets of first-time buyers who might consider this unit as their primary camcorder. First are tech-savvy young parents who are aware of the camera's limitations, but want to be able to grab a video with one hand while holding their baby with the other. The second would be techno-challenged people who happen to already own a blu-ray player (this may, admittedly, be a very small group).
Is there an early-adoption penalty? There is, always. Future cameras will be incrementally smaller, or slightly better in low light. But you only want an LCD so small, and the most critical limiter of low-light ability is the light-gathering ability - namely the size - of the lens. So until there is some great new video codec or a new chip technology, low-light performance won't be improved significantly without having a thicker unit. The most realistic expectation one might realize by waiting is having true 1080p resolution. But my kids get older, and less goofy, every day - 'damn good' now trumps 'even better' a year from now.
So do your research, read all the subjective and technical reviews you can, and remember the compromises inherent in the very smallness you seek. You won't find the best image quality and low-light performance unless you go HDV. But for a great second camera, you won't go wrong with the TG1.