Panasonic or Fujifilm?

[Bean]

Will be using it for travel photography

The 28mm of the Fujifilm would be useful for landscape photos, while the 420mm of the Panasonic would be advantagous for the occasional zoom-in details shot.

One can crop an image for a more magnified shot, but one cannot do anything but to buy an additional wide angle adaptor for a wide-angle shot.
If super telephoto is important, one must as well get the Olympus SP-550 UZ for its 18x stablized wide-angle Optical zoom.

The natural night mode and high sensitivity would be a clear winner for Fujifilm for night action shots!

Will be using it for taking pix of my kids,

OIS can only minimize hand shake but not movement of your kids, however the low-noise high sensitivity of Fufjifilm SuperCCD is able to minimize hand shake as well as the motion of your kids.

so would need one with good response time and short shutter lag.

For S6500fd, the half to full-press lag range from 0.03 - 0.06 sec.
For FZ50, the half to full-press lag range from 0.08 - 0.17 sec.

So for good response and short shutter lag, the Fujifilm would win here.

Sources:
http://www.dpreview.com/reviews/fujifilms6000fd/page4.asp
http://www.dpreview.com/reviews/panasonicfz50/page5.asp



You may like to read the reviews on dpreview.com where they compare the FZ50 with the S9600 in page 13 to 15.

http://www.dpreview.com/reviews/panasonicfz50/page15.asp

At ISO 80/100

Although both cameras are producing sharp, detailed and vivid results that will produce fantastic prints, if you look very, very closely you can see some minor differences; the FZ50 image does lose a little bit of the very finest detail and texture (something related, we would guess, to noise reduction), but overall I personally think it's a more attractive image (and there seems no doubt it's a better lens). The FZ50' color is certainly more appealing.

At ISO 400

At ISO 400 the superiority of the S9000's Super CCD sensor is obvious - noise (and therefore the amount of noise reduction needed) is lower. The bleeding reds and overall 'smearyness' of the FZ50 result look pretty poor in comparison but - crucially - the amount of high contrast detail retained is actually not that different (check out the fine text on the globe and batteries). Low contrast detail, on the other hand, has all but disappeared from the FZ50 image, meaning most of the fine texture in the shot has been lost. The sheer size of these images mean that the loss of detail is irrelevant for standard-sized prints. The bleeding and banding of the reds is still visible in small prints, however, and - when I produced a 6x4 inch glossy from this image - was the only thing that gave a clue as to the horrible mess Venus III makes of your pictures. You want to shoot ISO 400 or up? Turn the noise reduction down (or ideally shoot raw) and don't make big prints.

At ISO 1600

ISO 1600 is pushing things for both cameras, but the FZ50 is far worse, with an image that looks like a giant version of a camera phone shot. Panasonic's engineers obviously knew that everyone was putting full resolution high ISO modes on their cameras this year, and felt obliged to join in. My advice? Why not just throw your hands up in defeat and admit you're fighting the laws of physics, use pixel-binning and offer a 2MP high ISO mode that actually looks half decent and is fine for standard-sized prints? This is just clogging up my SD card with a smeary mess. I accept that shooting at ISO 1600 (which can be nice if you don't want to use the flash at evening social events) is always going to be a compromise, and I'd rather you got all those pixels to work together to produce a decent, small image than a terrible big one. There is also an ISO 3200 option (in High Sensitivity mode) that's even worse; it uses pixel binning then re-interpolates the image back up to 10 million pixels... madness!