see also:

• Micro Four Thirds system
• a catalogue of Micro Four Thirds lenses
• comparison of current Micro Four Thirds cameras
• microfourthirdsblogs

• both Panasonic and Olympus produce cameras and lenses for Micro Four Thirds and in general they are all cross-compatible, although some features may not be available on all combinations.
• Panasonic concentrates on HD video capability and generally relies upon optical image stabilisation
• Olympus concentrates on still and flash photography and all models have in-built image stabilisation but can also use optical image stabilisation when used with Panasonic OIS lenses.
• some older Olympus models have a special dedicated multi-connector accessory port below the hotshoe which allow various optional accessories:
  • VF-2/VF-3 viewfinders
  • PP-1 PenPal Bluetooth file transfer to smart phones with automatic resize to web-ready formats
    • 
    • automatically downsizes jpegs for web sizing prior to transfer to compatible devices using OBEX file sharing protocol (unfortunately, Apple devices do not use this protocol, so no Bluetooth transfers to iPhone or iPad, nor to some Android phones - see smartphone compatibility here (pdf))
    • has in-built memory which can store up to 2600 1920×1080 jpegs
    • not compatible with older PEN cameras which had Accessory Port 1 (eg. earlier than E-PL2)
    • review here
  • MAL-1 macro lite for macrophotography
  • SEMA-1 external stereo microphone adapter set includes stereo mic cable, port, and a stereo mic

• GHx = highest featured HD video enabled cameras with built-in EVF and oversized sensor for uncropped 16:9 still images.
• Gx = mid range version of GHx without the oversized sensor (also the original G1 did not have video capability)
• Gx0 = entry-level of Gx
• GFx = compact version without EVF (but optional add-on EVF available) - ceased 2016
• GMx = ultra compact, budget version - ceased 2016

• E-Mx = OM-D styled models
• E-Px = current most featured PEN model in the compact range without EVF but add-on EVF available
• E-PLx = PEN Lite range more compact version of E-Px
• E-PMx = PEN Mini, budget, even more compact version of E-PLx

• see comparison of current Micro Four Thirds cameras

• early 2012 - most of features on E-P3 plus 16mp sensor, built-in EVF, tilt OLED touch screen, new IS system, weatherproofed semi-pro body.
• my favorite camera!
• see Olympus OM-D E-M5 camera

• May 2013
• see Olympus E-P5 PEN (EP5/EP-5)

• early 2013
• see Olympus E-PL5 PEN Lite camera

• mid 2011 – external EVF, fixed OLED touch screen, the fastest AF for stationary subjects of any camera – not bad indeed making it a compelling buy consideration.
• official users manual (pdf)
• John Foster's review on biofos.com

• mid 2011 – minimally cut down version of EP-3 but still fast AF and you get a flip out LCD – a great value for money proposition

• mid 2011 – similar to, and more compact and cheaper than the E-PL3 but no flip out LCD, and loses a dial

• mid-2011 – minimally cut down version of GH-2 but still with fast AF but at much cheaper price point so is great value.

• mid 2011 – Sony NEX-like in size but has a triple core engine, fast AF, built-in flash, touch LCD screen. No hotshoe of EVF capability.

• late 2010 upgrade to the GH-1 with 24mbps HD video, faster AF, better EVF, and touch screen

• early 2012; enthusiast version of GF-3 style;

• early 2011 – a nice upgrade of E-PL1 with more controls, more options, new lens, faster AF, higher ISO, etc.
• single core processing engine instead of dual core as with the E-PL3, thus slower AF
• LCD screen is fixed 460K dot, not tilting
• built-in flash
• 3fps burst rate
• no AVCHD video, only 720p motion jpeg at 30fps
• no SDXC memory card support
• heavier at 362g

• late 2010 upgrade to GF-1 with smaller body, better HD video, faster AF and touch screen

• similar to the G2 but lower resolution EVF and no AVCHDLite, but only motion jpeg 720p

• 2010 updated version of the G1, adds AVCHD lite video (720p 30fps), touch screen for even faster manual focus assist and other functionalities, and ISO increased to max. 6400, mini-HDMI out, and front wheel dial moved to rear, new engine, new scene modes and MyColor presets

• similar to the E-P2 with an optional tiltable EVF in the hot shoe but adds popup flash with wireless remote TTL capability, dummies mode, dedicated video button, new sepia filter and faster AF
• as for E-PL2 but LCD screen only 2.7″ 230K dots, min. shutter 1/2000th sec not 1/4000th sec, slower AF, max. ISO 3200 not 6400, no iDetect to AF on a person’s eye, an older version of LiveView and a little lighter at 334g.
• no wired remote possible.

• similar to the E-P1 with an optional tiltable EVF in the hot shoe and some upgraded functionality
• as for E-PL2 but better build, more controls, orientation sensor, 8 art filters instead of 6, but significantly, no built-in flash and no remote TTL flash
• no IR remote but compatible with RM-UC1 wired remote via USB connector.

• similar to Olympus E-P1 but with faster AF, built-in flash, optional EVF (although no IS)

• the Swiss army knife of cameras – the king of the Combocams – video and still cameras, and the only one that does AF video well; 17Mbps HD video but older models can be hacked to produce awesome HD video.

• the cool, slim, compact, retro Olympus Pen-like, image stabilised Micro Four Thirds body – a great choice for photography enthusiasts mainly using manual focus lenses – AF is a bit slow compared with Panasonic bodies.
• the 1st digital Pen, as for E-P2 (ie. no flash) but no EVF option, only 5 WB presets not 8
• no IR remote but compatible with RM-UC1 wired remote via USB connector.

• the original, non-video, much cheaper version of the GH-1