If you would like to have a "Pull-quotes" button in your post editor, I highly recommend Frank Bueltge's Add Quicktags plugin. Go download that, and then import the settings file I have included in this folder (jspullquotes.wpaq).

It doesn't work directly in the Rich-text editor, but if you click over to the "Code" tab, the button will appear there. Personally, I use this plugin for several other custom tags I use regularly -- such as for post footnotes and foreign language <span>s. It's very handy. Danke Frank! :)

I may eventually integrate Quicktags directly into my Pull-Quotes plugin, but even then I will probably continue to use this Quicktags plugin.