Clarifying regarding the DoF control comparison. Let’s just do some quick sloppy math…
Panasonic f1.7 vs Ricoh f2.5 —> 1 stop advantage for Panasonic
m43 sensor vs APS-C sensor —> 1 stop advantage for Ricoh
so far we’re even.
But:
Panasonic 20mm lens vs Ricoh 33mm lens —> advantage Ricoh.
Also being that GXR has a macro lens, you can get closer to the subject and have more bokeh (although circle of confusion remains the same).

From http://www.dofmaster.com/dofjs.html, it shows that, @ 10 feet
EPL with 20mm/1.7 gives 3.96ft DoF
GXR with 33mm/2.5 gives 2.85ft DoF (I used a D70 as the camera, comparable sensor size)

IMO GF1, EP1/2, EPL, GXR are all fine cameras. We should be happy that they all have their strength and push each other to future improvements (or at least price drops!)

Based on dpreview, high ISO performance are amazing. It’s kinda hard to quantify how many stop you win against, but GXR image quality seem to be the best right now for a mirrorless (after Leica M9 or leica lenses mounted on 4/3). Hopefully, because it’s really expensive and this system is way less versatile as a interchangeable lens system.

And regarding the GXR’s better high ISO performance: Is it more than one step better? Because the m4/3 has a little over one stop larger aperture, so the GXR will have to use one stop higher ISO to compensate for this.