Hey folks. Ryan showed me this report while I was in the booth at the Scuba Show last weekend.
It is really a great review of the top 3 contenders:
http://www.reefphoto.com/kb.php?id=28
The lx5 with the tricky nauticam wet mate WA adapter, restores the native in-air FOV, and seems to really clean up the distortion and aberration you get shooting 24mm through a flat port.
(I would have thought that was impossible, with any kind of simple lens!)
Also, in private email, Ryan told me the the LX5 will work with the inon m67 lenses. And you just crop, or zoom, to eliminate vignetting, and you get equivalent FOV as you get with the oly xz1. So there is no reason to hesitate, if you want a compact digicam. Go LX5!