Summary: I am inclined to agree with reviewer RT about the V-Lux 20. I too own the D-Lux 4, and also a Nikon D3S. I was looking for something of Leica quality, but with the added reach of the extra zoom lens. I bought my D-Lux 4 a year ago with a then-in-place rebate from Leica, so I paid exactly the same for my D-Lux 4 as I just paid for the V-Lux 20, so they are worth comparing.
Summary: First let me start by saying I have never bought a digital camera that did not come with a memory card.(this is my 3rd). This $699 camera did not. I called Willoubhy's and they said I would have to buy one. So I bought an 8GB card for $42. It works fine for still pictiues but not for video. I called again and they said someone should have told me that I needed a HIGH SPEED memory card. I am waiting for Willoughby's to send me one.
Summary: Four years down the line I have just bought one on e-bay for £50. Not bad seeing that Leica charge£70 for a spare battery. They say in the 165 pages of instruction sheets that a non-leica battery might cause the camera to explode?