If you have Safari 5.0.1 or higher, you'll find in the Safari menu a link to Safari Extensions Gallery, a page on the Apple site that lists and describes extensions. Also in the Safari menu, choose Preferences and you'll see a new category, "Extensions," where you can manage installed extensions by turning them on or off, or click the "Uninstall" button to remove any extension.
Installing ScribeFire puts a ScribeFire button in the Safari toolbar (a black speech balloon). Click the button to open, in Safari, a window that enables you to add or remove blogs, create new blog articles, and publish to your blog.
You can also schedule when you want the blog to be published, or save it as a draft.
Looks pretty convenient so far. Except that adding images looks awkward. Click the "Add image" button and a dialog opens asking for the image URL. No images for this test.
When finished, click the "Publish Post" button. Testing, one two three.