Short, but sweet. Bring on Episode 2!
The bad: Again, the details in the storyline are not explained or highlighted. I get the feeling that Valve has no idea where to take the story, they're making it up as they go along. Playing time is short, but, as stated above, chock-full of great design ideas and taught firefights. New enemies, weapons, aspects of gameplay? Forget it. It's basically a short remix of everything that made HL2 great, minus perhaps the use of vehicles.
The ugly: there is nothing ugly about this game. If every company made games of this quality, we would spend all our free time in front of the computer.