My two cents here...
Back a few years ago when 5MP was king in the digicam world and I was getting ready to take the plunge, I remember much the same hand-wringing over the levels of noise in the Minolta Dimage 7i, which also had a killer lens and other features oriented towards the serious shooter. After much anguish, the guy at the camera shop where I checked it out said, "Shoot with it for 30 days and if you think it's too noisy, bring it back and not only will I refund your purchase price, I'll give you a discount on ANY camera you choose to replace it with." I took a chance and bought it.
I shot with that camera for almost four years and never once had a problem with noise at any ISO setting. Not one. Zero.
Yes, the noise from the Panasonic looked horrible in some of the test shots. Yes, there was noise in some of the gallery photos, but y'know something, the noise didn't look all that bad in the real world shots to me... kinda like the few times I used ISO 400 color film.
The feature set the Panasonic/Leica has (critical controls easily accessible and not buried in menus, image stabilization, and that gorgeous 16:9 ratio) in such a compact package is really making me look hard at this camera... and I mean seriously hard. I think this camera could be worth my hard-earned dollars come this Christmas.