If you’re looking to try out a new Micro 4/3rds camera, a good way to compare quality would be to take a picture with the same lens, same exposure, etc. An adapter is the only way to go about this, and a few have just shown up. And anyway, if you’re using the smaller hybrid SLR as a backup camera, having a lens adapter is a really good idea because it means you’ll only have to carry one set of lenses around. These Canon FD mount and Leica mount adapters appear to cost about $200 (I could be wrong), and like all adapters lose a little light; one forum poster put up some vignetting tests that looked a little savage. But then again I don’t read Chinese so I don’t know the circumstances.
The original forum post, with scans from a Japanese magazine (Nippon Camera), also shows Lumix DMC-G1s with Olympus, Pentax, and Voigtlander lenses attached. I’m still wary of the 4/3rds thing but being able to use my old lenses goes a long way towards making it a good buy.