I finally had a chance to use my XE1 a little bit more over the Thanksgiving holiday. The XE1 unfortunately did not make the wedding trip to the Bay Area as I was packed to the limit. So the wedding/honeymoon trip was all OMD with the PL25, 14/2.5 and 14-150. I also had the FL300R, which I used solely for fill-in purposes.
Ergonomically, even though the OMD feels a little cramped with so many small buttons, I found it much easier to use than the XE1. Moving the AF point around on the OMD is a one-handed operation vs. not only two hands on the XE1, but also having to pull the camera away from my eye when changing the focus point.
AF performance wise, there's no competition. The OMD trounces the XE1 in both speed and ability to lock focus in bad lighting conditions (with or without the AF assist lamp). Using the 35/1.4 and 60/2.4, I really don't see much difference between the XE1 and the XPro1 (pre firmware 2). I'm assuming that the purported vast improvement in AF performance on the XE1 and XPro1 is likely due to the 18-55 lens more than the cameras.
AF accuracy also goes to the OMD. There were times with the 35/1.4 that I had AF lock, but the photo still came out slightly out of focus. Similar to the XPro1, I found the C-AF to be a superior AF mode than S-AF. It's more accurate, and will lock on on less contrasty subjects in situations where S-AF refuses to lock. Only problem with C-AF is that the XE1 is constantly trying to focus even when the shutter button is not half-pressed. So that drains the battery quickly (and makes the annoying screw-drive motor noise).
I haven't downloaded the photos taken with the XE1 to my iMac yet. But they do look pretty good in the LCD and EVF. The LCD doesn't have as much contrast or brightness as the EVF. So images look different. I'm pretty confident the images will look great on the 27" screen of the iMac -- if I ever get to downloading them!