OpenVis Conf 2013
I did what no presenter should ever do: I watched my own talk.

My first visit to OpenVis Conf in 2013.
Filler Words
As expected, I could only focus on the flaws: the rushed speech, the odd phrases, and, most especially, all the filler words. In fact, I found 180 filler words in my 30 minute talk.
My Talk
Here are all 5,040 words of my talk.
My Stumbles
And here are all the fillers I used in those 30 minutes.
Um's, Ah's & Uh's
I almost exclusively used these three fillers. Um's and Ah's made up over 80%, with Uh's trailing behind.
Fillers Over Time
I hoped that all these blunders were toward the beginning of my talk. And the data suggests that fewer fillers are used as I get into it. Perhaps the talk started out rough and improved as I found my groove.
Ramping Back Up
Unfortunately, the trend does not continue. Midway into the talk my Um's and Ah's spike. I continue to use them pretty consistently throughout the rest of the talk.
The Cough Effect
My theory is that at this critical halfway point in my talk, I heard a dry cough indicative of the audience's waning interest. This caused self-confidence to collapse and forced me out of my groove.

A competing theory is that I just hadn't practiced the last half of my speech as much.
Best of Luck to Me in 2015
The world may never know, or care, but hopefully these insights improve my speaking in 2015. Though preliminary results aren't looking so good.