Don’t worry, it’s still there. Here’s a complete guide on how to make Ghosty visible again, if you’ve lost him.
Due to the heavy amount of support emails asking this question and the fact that there’s been a couple of new developments, We’ve made a post detailing exactly how to customize Firefox 4 and Ghostery to work in perfect, simple harmony. Here you go:
2) Click View>>Toolbars>>Customize… , find the Ghostery button in the available options, and drag him to any toolbar you have enabled.