It is indented differently in my code. I was actually surprised after pasting and posting it here that it displayed as it does, and I assumed something had removed some of the tabs. In retrospect, it probably has more to do with the fact that my text editor uses a different (user-adjustable, and font-related) tab setting.

I was just teasing. :P Could be / probably is that the indenting is tabs. They collapse in HTML—and many editors for that matter—by default. Tabs are wonderful where they are set properly, not so great in code portability. You can do a find replace with 4 (standard) spaces before pasting it into the post to get a more readable layout.