I was kind of left feeling kind of cold from this on the first time I saw it. This is the only episode I could skip in a marathon and not really miss seeing it, that's out of all three seasons thus far.
Now sure we get to see how Sam feels about John and how he thinks John may not even want to talk to him when they find him. Dean tells him it wasn't always John that was making life hard, and such. And we see how Sam can connect on a level with the home developer's son. With how the father treated his son, much in the same way Sam though John treated him. And the running gag in the episode about people thinking the brothers were a gay couple was funny, and the stuff involving the brothers squatting in one of the empty houses, was also good, and their banter back and forth, also good.
The parts of the episode I didn't like involved the curse that was causing the bugs to attack, and the bugs themselves. The computer generated spiders that attacked Linda were horrible, very fake looking. And as many people notice, at the end the major continuity problem with the time. It goes from being midnight to sunup in like five minutes, come on. It just seemed, to me, that the writers were told to come up with an episode as fast as humanly possible, without getting the chance to fix the rough spots first.