Perfect Day is about a day that is not so perfect (although the story is about as close to perfection as you can get). I think others have covered all the great points pretty well so I thought I would fill in a few background details that non-Oregonians might not be aware of :D
1. OMSI stands for the Oregon Museum of Science and Industry. It has a laser light show in the Planetarium (I think, it's been a while since I've gone). It's a GREAT way for people of Wyatt and Graham's education to meet and mix, people of all orientations and genders.
2. Bikes vs cars. Last year there were a series of horrific bike accidents, where car drivers who were either careless or outright murderous killed several bike riders, including one incident where a driver pulled in front of a group of bikers and deliberately braked suddenly on the downhill, causing serious injury and death. In other cases there were several hit and runs, like the one that killed Jase
. The amount of sheer hate directed toward bicyclists was shocking, victim blaming at it's finest.
This is a very enjoyable story and I hope that a few people find these details helpful :D