User blog comment:Greenberet69/Ezio Auditore da Firenze vs. Captain Jack Sparrow/@comment-4098900-20120512005310/@comment-4555900-20120514025435

This was supposed to be a gameplay trailer. So showing the musket pretty much confirms it as a useable weapon. Unless of course there were a lot of AC1 gameplay trailers that showed him using a crossbow. I know that CGI trailer did. But yeah, I'd expect it to at least be a pickup weapon from a dead soldier, like the spears in AC2.