Otime just mentioned on the "Battery for FZ1" thread that s/he doesn't much like the Panasonic SD Viewer software.

I'm not really in a position to judge, but thought I'd mention one piece of software that offers more in one field, namely "Exif Image Viewer". It's a freebie (try google search on : exif kowalski)

I like the idea of being able to do lossless image rotations (keeping the exif data) for originals which are then easier to see in my browser. Also it informs of the zoom setting your picture was taken with which I don't think all others do.

There are separate software threads here on Steve's Forums so suppose I really should look there before saying anything else...

Nonsense Norman. If you're interested in freeware software, check these out :

Photo album software and browsing, FotoAlbum at :
http://www.fototime.com/pages/products

Browse and display images; comprehensive exif data :
http://www.friedemann-schmidt.com/software/exifer/

Well-known freeware image photo editing software. Fancy selection of resizing algorithms :
http://www.irfanview.com/

Two I have already used a bit and can recommend from first hand experience :

Interpolating images up or scaling down with basic adjustments (contrast, sharpness etc) with a selection of algorithms. Output jpeg :
http://www.fookes.com/ezthumbs/?Easy%20Thumbnails=2600

Noise reduction software. Demo version outputs jpeg :
http://www.neatimage.com/

In the shareware software world, PMView Pro, http://www.pmview.com , also has loss-less JPEG rotates, is very intuitive and the filters/ gamma correction are very high quality and fast. Try the download version to see if you like it.

Regards,
Russell