Yep, the Safari logo in particular does it for me as they've attempted to make it look ever so slightly different ("Nooo, see this one's green and the compass dial is pointing at a TOTALLY different angle"). Just reminds me of the rather awful OS X-like skins you see for Winamp or basically any skinnable application. Bleh
Which part of the theme? The netscape navigator icon was just a circular logo with a big "N" and the icon for the old Communicator browser was a Lighthouse - which is only vaguely related in a nautical\navigatey sort of way