Web designer and blogger John Faulds recently reviewed our open source content management system, Hero Framework.  I suggest you check out his review, but here's his conclusion (we're working on the multi-file upload system, John!):

As I mentioned earlier, without the requirement to attach multiple images to entries, the entire process of installing Hero, learning enough about how it works to get the job done, and building the site would’ve only taken a couple of hours. The gallery module thing threw a bit of a spanner in that works. Because of that I probably wouldn’t use Hero again for projects that require adding multiple images to lots of entries. But for sites that only have a single gallery, or a single page of galleries, or for lots of other scenarios, I think Hero would be a good choice. Those other scenarios also include the ability to do ecommerce which I haven’t tested out, so it’d be good to hear from anyone who has used it for that purpose.