Not a guru but I've been a hack photographer for a number of years.
I'd stay away from the Lumix. While it does have the nice lens, they've consistently gotten poor reviews due to excessive noise in the images. So while the lens is nice, the processor is kinda crap. I haven't researched cameras in at least a year, so they may have fixed some of the issues, but from what I recall, it was not much of a deal in the end.
I have found this site to be useful:
steve's digicam reviews I've no connection to the site, I've just used it as a source for info and found it helpful.
As others have mentioned there is more to choosing a camera than just the pixel rating.
- What type of battery does it use?
- What type of memory does it use? -- I ended up with a Sony as it's got a nice Zeiss lens. I uses a proprietary batter and it takes Sony's proprietary memory sticks. Both trade-offs I was ok with as I liked the camera. Though ultimately it is a little small for my hands.
I'd do some research, make a short list and get to a store and handle as many cameras as I could. Take some shots with those you think you might like. See how easy or difficult the camera is to hold, to hold steady and get a focused shot, to shoot quickly with -- sorta stand there and try it out. How long does it take to power on? Does it just feel right in your hand?
Navigate through the menus on the camera. Are they easy enough to use or is stuff hard to find and do? If it's hard to change the settings on the camera in the store, it won't get any easier out in the world...
As for brands, I guess I'd recommend Canon, Nikon, and Sony, though not in any particular order. I own a canon digital slr and sony point-and-shoot. If money is no object you might consider Contax or Lieca proper...um yeah.
- The software thing, i don't find to be that much of an issue. If your pc doesn't have a memory card reader they're easy enough to get, and when the memory cards are installed into a pc, rather than from an attached camera, they're a little easier to manage. And often times the image download process is faster. Most of the image management software I've seen from camera manufacturers is pretty poorly designed. But take into account that I design software interfaces for a living. So ymmv.
