Played through a bit more of this this morning. There was a huge section on an air boat thing, which did seem to go on for longer than it really needed too, ending in a fight with the helicopter that had been chasing me for most of the game so far.
After that, I found Eli’s lab, with Alyx inside, and spent a while playing catch with Dog – a robot. I could play catch, since I had been given the Gravity Gun – aces!
Then the Combine found us in the lab and I had to leg it down towards Ravenholm, which I thought was a place in World of Warcraft.