According to Olympus' website, the 'X' in 'XZ-1' is a brand new 'Creator' series of cameras, so named to separate it from the rest of Olympus' compact cameras. And stand out from the rest it does, with a list of impressive credentials. It has a 1/1.63" CCD sensor, which is larger than usual for a compact. For comparisons' sake, the popular Canon Powershot S95 uses a 1/1.7" sensor. Coincidentally, the Panasonic Lumix DMC-LX5 also uses a 1/1.63" CCD sensor. The XZ-1 also has fully manual controls, as well as an accessory port equal to those found on the PEN E-P2 and E-PL1. This latter means that the XZ-1 can use whatever accessories its bigger brothers can.
And the most exciting feature about the XZ-1 must be its f/1.8-2.5 i.Zuiko Digital lens with a 35mm equivalent focal length of 28-112mm, which makes it the first compact with a Zuiko lens and the fastest glass that can be found in a compact camera today. To put things into perspective, the Canon S95 goes f/2.0-8.0 at 28-105mm, the Panasonic LX5 does f/2.0-3.3 at 24-90mm and the Samsung EX1's lens opens to f/1.8-2.4 at 24-72mm.
(If you're wondering what all these numbers mean, a lower f-number simply means the lens' opening – or aperture – can open wider, allowing more light in and letting the photographer shoot at a faster shutter speed compared to a lens with a smaller aperture, especially in low light. That's why they're called brighter or faster lenses. Another consequence of shooting with a wider aperture is that you get blurrier backgrounds, which brings focus to your subject and adds to the aesthetic of an image.)