Not concerned about budget. Don't care so much about the number of functions. I just want the highest quality photos. Or should I wait for the next OM-D to come out? I presently have 12-40mm PRO with my E-PM2.
Photo-quality wise, they are all, for all intents the same - and throw the GX7 into that mix as well. You should make the decision on the basis of features and ergonomics and budget as you prefer them, but I would also suggest that if you care about a viewfinder, the E-PL7 should be dropped from your list, and if you don't, it should be near the top of your list.
I think the OM-D M1 would be the better match to your 12-40 PRO. It is a heavy lens and I did not like it on my OM- D M5. OM-D M1 has better IBIS compared to the E-PM 2. You might find that helpful for sharper pictures in bad light.
a combination of what doug and Rolle wrote. basically, the pictures from all cameras should look the same. Note the fact that M10 has a 3 axis, while M1 has 5 axis stabilization (PM2 has 2 axis), so if shooting with slower shutter speeds, pictures from M1 shuld THEORETICALLY be sharper. Also, shutter shock could be less notable in that heavier body. M1 should have the best balance with heavier lenses. That said, M5 Mark II SHOULD come out during next year, but i doubt it will be have anything above what M1 has, in order not to kill the sales of the E-M1, just some catching up (1/8000, wifi, focus peaking, better EVF). And that thing should be prettier than E-M1, if that means anything to you.
High quality photos is meaningless. What photo subjects are you interested in? Different cameras may have different functions that are more suitable to specific applications, for example different AF capabilities, different bracketing capabilities, and so and so forth. You already have a very good lens, so you need to think about what you take photos of, how big you print them, etc. It could well be that your current camera is more than suitable...
The first criteria I consider is: do I need an EVF of not? The EVF costs and takes up a lot of space. Then: do I need any special feature? Is weather-proofing a must have? Or is the smallest size? Do I shoot a LOT of sports where the EM-1 AF could be a little better? Do I need 1/8000s shutter speed? Am I going to use wi-fi more than once in a year? Do I want the most comfortable grip? Do I need "live bulb" for night photography? In my opinion there is not real technical difference in IQ between these cameras or the Panasonic of the same generation. The next generation sensor (not yet announced nor rumored about) should be, as usual, better, but hardly revolutionary. And what you get "in the field" is hardly related to the tech specs that you get in a lab.
The first criteria I consider is: do I need an EVF of not? Don't need, perfectly fine with screen. Is weather-proofing a must have? Yes, -40C here in Quebec, Canada, love to capture the festivals here. And I don't like to postpone photoshoots in the rain because my lens is weatherproof but my body isn't. Or is the smallest size? As long as it's not those DSLR monsters. Do I shoot a LOT of sports where the EM-1 AF could be a little better? I shoot boxers, so punching and stuff, a lot of action. Do I need 1/8000s shutter speed? Do I? Am I going to use wi-fi more than once in a year? Yes, absolutely. Do I want the most comfortable grip? E-PM2 thumb grip isn't the best. Do I need "live bulb" for night photography? Yes, I like making those light trail pictures. What camera suits me? I also want Auto ISO.
you're kind of answering your own question right at the weatherproofing Bub... no need to go further. E-M1 is for you.
EM-1 is your best option: is the only one freeze-proof (and few lenses are). EM-5 is dust/weather proof only, EM-10 is not. You "need" 1/8000s shutter speed to shoot wide open in bright daylight with fast lenses. In my opinion it is not a must have: use 1/4000s and close the lens just one extra stop (or use an ND filter). All OM-D cameras have Auto-ISO for all auto modes by default (P, A, S, etc.). To use Auto-iso in Manual mode too you need to unlock it in a menu option. Regarding AF: your distance from the boxers is not going to change much during the match so any AF should work with no problems. If you shoot motor sports, birds or something where the subject distance from you changes a lot the PDAF of the EM-1 should be better. The EM-1 is the bigger of the lot, but is about the same size of an EM-10 with the extra grip added. http://camerasize.com/compact/#482,289,521,ha,f The only advantage of the EM-10 and EPL-7 (coming in a couple of months) is size (and price).
The best choice from what I can surmise from your information is the Olympus OMD EM1. Go out and buy it now. Then go out and shoot with it and enjoy.
No problem. with the amount of volume they do on that sight, there are typos from time to time. It is always a good practice to check multiple sources, as you've done here.
It's coming: http://www.43rumors.com/ft5-first-image-of-the-new-olympus-e-pl7/ Basically, the EM-10 innards with an E-PL5-ish body.