This great camera is perfect for whom prefer to compose with the camera in the eye like God wanted, not at an arms length. The image quality is on par with any under US$1500 DSLR. My D90 is gathering dust because if I'm going out, I allways, instintively, grab the G1. It balances very well with the 14-45mm (28-90 equiv.) lens, which is VERY small for DSLR standards. This camera does it's work occupying 60% of the space and weight than an amateur DSLR. It's easy to learn, and it's intelligent ISO and aperture priority modes make it a very quick "decisive moment" camera. The 20mm (40 equiv.)f1.7 it's a dream lens, more than "tack-sharp" at about four ounces!
The electronic viewfinder isn't clear like an optical one, but it's BIG, full frame size, without the dreaded "tunnel effect". It can, if you want, get a highly zoomed center square that makes manual focusing, when you want it, a much simpler task.
The electronic viewfinder is the future of the industry: It turn practical to build much smaller cameras, "in the viewfinder" histograms (it's live view), center "zoom", no mirror slapping, which permits to use lower speeds without blurring, and less moving parts. It's a photography camera: I didn't pay for a movie-capacity that I didn't need or care.
The micro four thirds Panny Lumix G1 is the "goldilocks" camera: just right.
Even if the G1 is standing daily abuse very well, the build quality, materials, switches and knobs of my Canon G11 and Nikon D90 are better, firm, solid.
Get more detail about Panasonic Lumix DMC-G1 12.1MP Digital Camera with Lumix G Vario 14-45 mm f/3.5-5.6 ASPH Mega OIS Lens (Red).