Into m4/3rds "one more time". Recommendations needed.

I agree with most other posts that these cameras are getting out of date, especially if you're used to bigger SLR sensors. On the other hand, if you are looking for a good deal on used cameras, I expect you won't find a lot of disillusioned OM-D or G5 owners getting rid of their gear this soon but you might find a deal on a Panasonic G3 with a modern sensor and good video caracteristics - some better than the video-oriented GH1 you mentioned. For even better video, the GH2 would be perfect.