If you plan on doing HDR... Plan on Purchasing Photomatix software... its the best available... Currently.
So what you really need to know about these two cameras... is do they have RAW format, or even more importantly, Exposure Bracketing...
I have used neither of these cameras, but from experience, I find that the Nikon is a bit soft, and that the 10Megapixels sensor, is too low to successfully create HDR photos from 3 bracketed shots, unless you are on a tripod, since you will lose a lot of photo after re-cropping... effectively turning a 10 MPx photo into a 7 mpx photo... not fit to print.
As for the Pana... I have never heard anything negative about this camera... aside from the fact that the sensor can be extra grainy in low light situations.
My recommendation... if you are interested in dropping $1000... and want HDR... buy a TRUE DSLR... and never look back.
