I spent some time researching solutions for automatic social bookmarking submission and Social Bookmarks Demon was script with best features.
I paid $169 for it and after all day of testing I found that it's not working like author wrote on sales page.
Inside admin panel there is some kind of report option that can just tell you that your URL is submitted, but can't tell on what sites.
So, I went on each site (listed on sales page of software), checked is my URL there and found that it's posted only on few of them.
After few emails sent with bug report I asked for refund, but no answer.
When I send refund request via Plimus, vendor answered
"full refund can be issued only when software fails to operate after support staff investigation"
But on sales page he wrote:
I'm so proud about Social Bookmarks Demon, that I offer full money back guarantee for 7 days. For example, if Social Bookmarks Demon will build so many backlinks that your servers will not handle premium traffic anymore, just ask for full refund!"
I also found that owner of this site made few fake reviews on squidoo and blogs around, so it's possible that he will answer on this post with some fake account claiming how this software really works.
Also if you check site of similar product Social Bookmarks Submitter, you can see that it has the same design and I think that is the same owner like Social Bookmarks Demon.
Be aware of this products!