The G1 is a great camera and impressive accomplishment as the inital :43: camera. There is no "Rev 1" feel about it - it is very polished, without any major problems having shown themselves in the postmarketing period.
I think it offers the best value in :43: land. Take a GF1, remove the video, add a kickass EVF and flip/twist LCD, and drop the price a lot?? We G1 owners are getting a
lot for their money.
The initial knock on the G1 was that it was too big, not exploiting the size advantage of having no mirror, and that it looked unnecessarily like a DSLR. Although the latter is true, that there is no need for it to look like a DSLR, I think time has shown that the design is sensible. Lookng at the height of the other :43: options with EVF, one can see some of the logic in the G1 design:
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That is not to say that they couldn't have designed a better looking "rangefinder style" camera, a la DMC-L1; only that the current design makes sense as well.
The other knock on the G1 is that it isn't that much smaller or lighter than a small DSLR. This is true, but it offers all the other advantages which are inherent to the :43: system: WYSIWYG view on both LCD and EVF, class-leading live-view usability, most compact available AF lenses, sophisticated AF system (far more AF points and even coverage than any similarly sized DSLR), metering options not possible with current DSLRs (metering based on faces detected in the frame), etc.
When I hold my G1, I'm reminded by how well thought out this camera really is. The little touches stand out, for example, the way the LCD display turns off automatically when I raise the camera to my eye, the way the diopter control is recessed to avoid accidental bumps, the manual switches for focus modes and self-timers, dedicated ISO button, and the list goes on.
In short, if you do not want video capability and don't need to the smallest size :43: camera, the G1 gets my highest recommendation!