About 4 people have asked me off-line "what about the focusing?". I don't have enough real world experience to say one way or another if it is going to work for me. I can say that it's not horrible. You can put it in a mode where the camera decides and that's not bad or you can put it in a mode where you decide the focus point. Both seem useful. Both seem pretty quick in situations that I am likely to actually want to make images. It focuses fine in situations where I need image stabilization at 1600 ISO at f 3.5 so that is probably fine.
I can tell you that the way continuous auto focus works is annoying. I won't describe it and I have no idea if it works in reality but I probably won't really use it. It's noisy, disconcerting, and you have to trust that it's going to work. Not really what this camera is for in my mind. I'll test it soon just to see. I am probably not going to use continuous shooting either. Just like I have no desire to put a motor on my Leica M cameras.
The manual+single AF is actually very useful on the E-P1 once you get used to it. when you turn the focus ring on the lens the camera automatically zooms in on the focus area that was used for the AF in the first place. In situations where you are likely to need that kind of precision verification (not happening real fast) It's not a whole lot different than using my D3 with AF+Manual. Just remember you have to keep the shutter pressed in half way while doing the manual adjustment or it will refocus when you take the shot. You can decouple the focus from the shutter and use the AE/AF lock button to focus instead of the shutter release but in practicality that has not proven very effective for me on this camera (it is on my Nikons but for some reason - maybe the buttons are too small, it's no on this one).
If you are "testing" this camera you may find it annoying that the auto focus areas are so large. The reality is that inside that large focus area the camera chooses a really really small focus area - about as small as the 53 area mode on a Nikon. You just can't pick them yourself. I say you might find it annoying in that you are surprised by what tiny point was actually used vs what you wanted if you use the AF on really close up stuff where you wanted the tiny area to be different than what the camera chose. That is what the manual+AF mode is really for. If you are at more normal subject distances it probably doesn't matter a whole lot.
Olympus says that it focuses on the closest thing within the AF area box. In reality it seems to be random if there are multiple things all at similar focus distances with in the displayed focus area. Like I said - you can play "gotta" and be annoyed with testing or you can take pictures and see how they turn out. If you are really close up use the manual override to see or use that zoom view mode. The image at the top was real close to minimum focus at the longest zoom setting at the widest Aperture. This is a 100% crop. I just selected the focus area and let the camera do it's thing. The sharpening was set to "normal" for this out of camera JPEG.