Are you using the Quick Entry one or the other one? If you are using the straight to in-box, you probably won't see much happening. But you may want to look at the Inbox in OF to see if it put the thing in there.
I got the the URI handler bookmarklet to work in Firefox, after using kaijin's fix. However, I can't get the keyboard shortcut to work. When I press it, the Bookmarks menu item lights up for a second, but nothing happens…