I've just been having a look around our competition's FHG's and noticed in general that many keep the image sizes pretty small; for example nubiles typically use 762x507
We always keep the images on our Hosted Gals at the size they are in members area (1752x1220 or larger) - theory being if a surfer looks at a gallery he is more likely to be swayed by seeing them full size then cut down versions.
Feedback from members shows they like big images.
For example a typical TeenDreams Hosted Gallery:
http://www.teendreams.com/tgp/20/julia/
What do you think, are we wasting bandwidth, or do you think its better to keep the Hi-resolution images?