I don't see why anyone would want to prevent someone from being able to save the image to enjoy offline.  I do implement a very similar feature on my own website to encourage people to register (for free) and download the high-res versions offered instead (since the displayed versions are more highly compressed and scaled down for easy browser viewing on lower resoultions and as a measure of bandwidth control).

I like to save images often because sometimes people delete their galleries, or Renderosity deletes items from their galleries, or hell Renderosity itself might disappear into the void (god forbid ;) ).  I also have a laptop that I take offline frequently and I like to sometimes be able to go back and look at some of my favorite images without having to be connected to the internet.

Not everyone who wants to save artwork wants to steal it, and in the end there's always the Print Screen button.  If Renderosity implements some anti-saving measure across the board I believe it will simply be more of an annoyance to those who enjoy the works here than an actual deterrance to thieves.  There are more effective ways to prevent theft, such as signatures and watermarking (though invasive watermarks are an even bigger pet peeve of mine b/c they destroy the artistic quality of the image).

On the topic of the new homepages, I think they sound great and can't wait for them to arrive!

¤~Giolon~¤

¤~ RadiantCG ~¤~ My Renderosity Gallery ~¤