I love all of the Olympus lenses. I have the new 12, 17, 45, 75 and for a 25 I have the Pana Leica 25.
I haven't compared them in a science setting, but all of the lenses (if the camera really is a 2 to 1 crop vs. 35mm seem wider than the full frame 35mm dlsr camera and lenses.
The 75 on the 4/3 which should be a 150 on my Canons seems to offer more room (for a better word) and less squeezed, the 45mm more than a 90 on a Canon.
Don't know how to explain this but it does.
I really love the OMD, though they really need a 8,000 sec. shutter for outside in sunlight or some built in ND's.
The OMD is not a pixel peeper camera because next to even to most APS C cameras the file won't hold up as well in micro examination, though it produces a different look, somewhat more natural and less refined, which could be that the camera is smaller and allows for that type of photography.
Don't know, but I really like using it and have and will on certain paying projects (used it today, yesterday, last week, etc.).