I've been rather interested for the DMC-GH2 for a while now. It's a comfortable camera body with a sizeable and growing count of lenses with a passion for video. Okay, passion may be a bit much but this article suggests exactly that.
The fact that video doesn't quite have nearly as much resolution as still photos do (for now), suggests that micro Four-Thirds bodies should be quite capable of doing good video. However, this body in particular has a particular strength, a multiple aspect ratio sensor. It doesn't have to compromise on aspect ratios including 16:9, 3:2, or 4:3 and I believe, 1:1. That's an advantage.
Zeiss have already released several cine lenses and I read that Schneider would be doing the same with their own products for the system. Mostly, this was for the more impressive Panasonc AG-AF100 but they apply to any camera body that has the micro Four-Thirds mount. Of course, many people stepping up from point-and-shoot models won't be interested in manual focus but just want to capture videos of their child or pet. The lenses are also priced so that only the most interested will be willing to pay.
Panasonic introduced some power zoom lenses, similar to what you might have used on a point-and-shoot digital or Olympus' IS-series of integrated 135 format cameras way back when. They provide home movie convenience with some good optical quality. Notice that I'm not saying great optical quality. Panasonic and Olympus have gone on record as saying that micro Four-Thirds products should stay small. They don't want to scare away users the way they did with Four-Thirds. Keeping things small and light means limiting optical quality. I'd like a better compromise, but I'm not the target audience for their products.
The GH3 has been rumored to have better dynamic range and light sensitivity. Considering the GF5, it will likely have a revised processing engine, as well. What surprised me was that a rumor suggested a slightly lower pixel count. 16.x MP isn't exactly high or low, but I can only imagine that they're willing to sacrifice pixels in order to increase dynamic range and to reduce effective noise. It may end up that there will be a higher pixel count and the newer sensor will use better techniques and op-amps to reduce the noise. I'd think that they will increase the sensor output speed to increase auto focus speed and performance during sports photography. (In reality, the continuous auto focus is some interesting predictive auto focus and it predicts that I don't want to focus in the right places, but only sometime.)
Given that I've seen a number of professionals hanging 2 or 3 SLRs around their neck, wouldn't they be happier with 2 or 3 GH3s around their neck, if it meets all the criteria, including better lenses?
I can see the point where Olympus and Panasonic are going to realize that their current lenses aren't a match for the sensor quality and they'll have to design new lenses similar to Olympus' SHG line or say that they don't care, that it's someone else's market. (It's sad that the Panasonic 35-100mm f/2.8 lens just isn't a substitute for the Olympus ZD 35-100 f/2.0. Besides the image quality, I find it too small.)
It's an interesting time for digital photography, and given the complexity of a reflex camera, it's a wonder that mirror-less cameras haven't been popular until now. I'm interested, but only just.
Update: Panasonic has apparently scheduled a meeting partway through July. There seem to be reductions and/or discounts in certain equipment at the moment, as if they're at end of life. There have been a number of suggestions that several lenses are going back for a makeover. I'd think they were going to add their Power O.I.S. and weatherproofing, but they may also try to reduce size or correct their sometimes too high chromatic aberration to work better with Olympus bodies.
It's not a total surprise but the G5 has been introduced without the GH3. Since the G5 is using the possibly same 16 MP sensor from the G3, I wonder if it's really likely that they'll not change the GH3 sensor either. In a way, it's good for them to get a handle on image quality at a certain resolution, especially since they're fighting larger sensors for stills. How patient can we be?
Update 2012.12.22: People have been receiving their GH3 bodies somewhat slowly. It seems as good as anyone could hope. There were a number of complaints about the size, but it's smaller than Olympus' E-1, which started Four-Thirds. I'm finding the E-1 a bit small for the Olympus Zuiko Digital 14-35mm and 35-100mm lenses, which makes sense why the E-3 and E-5 were larger. I'm really not certain about using the GH3 with an adapter. Sources say that a upscale Olympus body is coming toward the end of 2013, and there has already been an Olympus patent showing an adapter with phase detection auto focus. For me, an OM-D sized body won't do it. The OM-1N I had was slippery with the 75-150 f/4.0, so imagine a body that size with a lens much, much heavier and bigger. On the other hand, my E-5 and 35-100mm and FL-50 slid off a plastic seat onto the pool deck and kept working, so maybe it won't matter.
Update 2013.02.26: I received my own GH3 and it's been interesting--better than expected in many ways, but still not great for photography although good. I still find the Olympus E-5 to be a bit better, and much more predictable. The Olympus MMF-3 adapter is quite helpful in getting the SHG and HG lenses attached to the GH3 for higher image quality.