20mm f/1.7 is the one "must have" :43: lens, in my opinion. Image quality is great, price is reasonable, and it's fast enough for good low light performance. That said, the 14mm has really got me thinking about the potential of the :43: system, especially now that other large-sensor mirrorless systems (e.g., Nikon) are coming out. The thing makes the camera/lens (in my case, a GF1) so compact, but performances is still very good. If they find a way to build in a decent viewfinder in the traditional rangefinder location, they'd have a modern CL/CLE type system (obviously not a rangefinder, though they could, or could go hybrid like the X100.)