The R-D1 is pretty much the only game in town for digital rangefinders right now
... the Leica Digilux 2 ...
The Digilux 2 is not a rangefinder; it does not have the defining feature of the rangefinder's split image focusing system.
Apart from Leica's tenuous involvement in that fine Panasonic product, it has no more connection to rangefinders than any other digital camera with a peep-hole (not through the taking lens) viewfinder. I liked my Olympus C-2040 and its fine f/1.8-2.4 lens, but I never called it a rangefinder.