Alan Ernst

Looking at the specs, this could be a great lens and long overdue! If optical quality match that of major manufacturer's comparable f2.8 zooms, then the price indicated could be justified.
I do hope they get quality control / consistency right this time round (a big issue with the 12-35mm X). For this kind of price, I want to see corner to corner sharpness throughout the zoom range, no vignetting, and minimal distortion / CA.
What I like about the specs:
- size/ weight comparable to the dust sucking, slow 45-200mm, but the 1-2 extra f-stops will reduce need to resort to high ISO's, which is an issue with m43.
- love the environmental sealing and non-rotating / non-expanding barrel
- happy to see the same filter size as the 12-35mm f2.8, which means you can use the same filters on both lenses.
Hope they will offer a matching tele-converterAND come up with a fixed, top quality 10mm f2.8 wideangle lens w. filter thread a.s.a.p. to round out their range of quality lenses.

By increasing size / weight (+25%) and canning "multi-aspect sensor" the GH3 loses 2 key advantages over APS DSLR's. No matter how they tweak processors / sensors, a smaller sensor size will always be a disadvantage compared to APS-C or FF sensors. Panasonic want to produce a hybrid video / stills camera, which unfortunately is becoming too video based and less suitable for stills photographers who need a feature rich camera in a compact package.

Negatives IMO: base ISO 200; (partial?) loss of multi aspect sensor; too video oriented; bulk, TOO many buttons / reduced ergonomics due to button/control placements and price. Other shortcomings of GH1/2 still not addressed.

I see positive gains with sealing, better screen, dual control wheels and a larger battery. Better DR / high ISO performance / faster processor??? Past claims in this regard were always way exaggerated, so would have to test this. In-camera HDR is clearly no substitute for a good sensor.

No GH3 for me, thanks!

Pocketable indeed! The larger sensor is a good idea, but I think 12MP would be more than sufficient whereas a 5x zoom in the 24-120 or 25-125 range would have really set it apart from the other enthusiast compacts in the crowd...

It is high time Panasonic / Olympus release a top notch standard zoom to rival the optical performance of the best 24 - 70mm lenses out there. So far, I have not been thrilled with any lenses in the Lumix line-up (including the two PZ X's). Corner sharpness of the Olympus 12-50, which otherwise would be a really nice lens, is also disappointing...
I don't mind paying more for a quality product, but it better be an impressive performer: superior corner to corner sharpness at all focal lengths from f2.8 - f16, minimal CA, light fall off and distortion and no vignetting when using filters and filter holders at the wide end.
The sealing must be more than just along the lens mount - some of the Lumix lenses are big dust suckers (45-200; 100-300; 14-140), so they better address this issue or it won't be worth the price!
It would also be nice, if they looked at some consistency in lens threads and had made this a 62mm instead of 58mm diameter (or same as the 35-100mm lens that is planned).