After using the GH2, I don't see much need in an optical viewfinder in a HDSLR anymore. The advantages of an electronic viewfinder are plenteous: You see what the camera is seeing, Exposure, White Balance, 100% view, it is eye level and does not black out when shooting video and you can hold the camera with out a rig. This new advancement in viewfinder technology makes the viewfinder better than a 720p display. This article is from Gizmag:
“Digital camera technology has just taken a huge leap forward with the development of a microdisplay panel that's millions of pixels beyond what is currently used in the highly detailed electronic viewfinders of Fujifilm's most recent X-series cameras (X-S1/X-Pro1), and more than double the panels in Sony's latest alpha and NEXcameras. MicroOLED's new bright and detailed, low power OLED panel has been viewed by a number of industry pundits as the final nail in the coffin of the optical viewfinder.
Even though electronic viewfinders (EVF) allow photographers to access lots of important information like exposure or white balance while framing a shot, and see what the application of different settings will look like on the fly, professionals and serious users still seem happy to continue with optical. Reasons offered for sticking with tradition include a lack of dynamic range, noticeable lag while the digital image is processed and concerns about the power needed to drive electronic panels.
The image quality of Sony's recent consumer-level XGA OLED EVF panel developments, in particular, already seems to have stunned some of the critics into silence, but now MicroOLED has entered the fray with the highest pixel density OLED microdisplay available on the market today. The new 0.61-inch (diagonal) OLED panel has a 5.4 million pixel density and a sub-pixel pitch of 4.7 by 4.7 micrometers. It comes in both 16 million color SXGA (1280 x 1024 pixels) and monochrome (2560 by 2048 pixels) formats, and is also said to have eliminated any spacing between pixels and benefit from 96 percent uniformity.
The high resolution image reproduced on the display has a 100,000:1 contrast ratio that should pick up many of the subtle tones in a scene that are missed by other EVFs and, perhaps most importantly, it can be driven with as little as 0.2W of power.
MicroOLED is looking to market the new panel for use in head-mounted displays used by surgeons, professional cameras and camcorders, and night vision applications.”