When the new firmware is released, some people will try to decipher the firmware, and try to make changes to it. Most likely they will not be able to add genuinely new features, but perhaps they can make changes to parameters like the video bitrates. This is usually called "hacking the firmware". The GH1 was popularly hacked, giving the possibility to use a higher video bitrate.
Panasonic can also, if they invest the time and resources, add new features to the camera with a new firmware upgrade. Here are some of my ideas for new features, or changes to existing settings:
Dropping RAW images when the buffer is full in continuous drive mode
The GH1 and GH2 were plagued with horribly slow buffer clearing speeds. The GH3 improves significantly on the predecessors in this area, however, you may still run into problems with taking consecutive images fast enough for when recording both RAW and JPEG images, even with a fast SD card.
My suggestion is a new setting, in which the camera only records both the RAW and JPEG files as long as the buffer is not full. When the buffer is full, it could revert to only recording the JPEG image. That way, you can sustain a high frame rate for a longer time.
And you can use one single mode at all times, without having to change mode when you need to take a lot of consecutive images. Such a feature will give you access to the RAW images most of the time, except when you happen to need a long series of consecutive images.
Remove the electronic shutter ISO 1600 limit
The GH3 has a very useful electronic shutter feature. However, it is limited to ISO 1600. Perhaps Panasonic have introduced this constraint for a reason, there might be some adverse side effects when using higher ISO. But anyway, allowing for higher ISO in electronic shutter mode could be useful, even if there is some risk of degrading the image quality slightly.
Auto ISO available in Manual mode
In the Manual (M) exposure mode, the auto ISO features are dropped. This is a strange choice to me: If the auto ISO settings were available, you could set the aperture and shutter speed manually, and the camera would select an appropriate ISO to match the exposure, if possible. If you need to set the ISO manually in M mode, that is of course still possible.
The Pentax DSLR models support this feature, and I think it is very useful. This could easily have been fixed with a firmware upgrade.
Focus peaking mode for manual focus assist
Some Sony camera models feature "focus peaking", in which an outline is highlighted when an object is in focus. This is useful for manual focusing, especially during video recording.
A Panasonic engineer was quoted saying that this could not be done with the GH3, due to image processing constraints. Perhaps this is true, but I still think that some focus peaking feature could have been implemented into the GH3.
To add to the confusion, a Panasonic engineer has later been quoted saying that the focus peaking mode could be added with a later firmware upgrade, but not now in March.
Do you have ideas for other features Panasonic could cram into the GH3 using a firmware upgrade? Please suggest in the comment field below!