You can upload as many images to your website as you want to... and you can group your images into an unlimited number of galleries in order to make it easier for visitors to browse by common themes.

There are absolutely no limits whatsoever.

Examples:

http://dave-welling.artistwebsites.com/galleries.html

http://juergen-roth.artistwebsites.com/galleries.html

http://scott-gould.artistwebsites.com/galleries.html