This is actually the third pitch. Unless you counted the scramble from the top 'O the second to here as a pitch. He is half way up the third to a set of 3 chains which then begins the fourth pitch. The fourth pitch by the way is the only section rated at 5.8 EVERYTHING else is a 5.6, if you disagree with me go scurry up the fourth and tell me it was just as easy as the previous three.
Ever wondered where the name penta-pitch came from with that route only being 4 pitches? Dude is on P4, end of story. Why you'd do this route in more than 3 pitches is a different question which should be addressed immediately in a thread. Along with a heated argument about the 5.6/5.8 rating (I disagree with rth on that)
I agree that this is definitely the 4th pitch. However, like Boissal said it is kind of confusing why you would make this climb in more than 3 pitches anyway. I just climbed it last weekend. When my partner and I got to the top we didn't even realize it was the top. We were looking for the last two pitches. The first pitch is easy to identify, but the second and third run together. It is also very easy to link pitches 4 and 5. The quality 5.8 maybe even 5.9- face climbing is in the 5th pitch past the 3 chain anchor.