Blue emails Simon and admits that in his curiosity about Simon's email address (hourtohour.notetonote), he searched for the words and learned that they're from an Elliott Smith song. Blue says he then listened to a bunch of his music and really likes it, and thinks the music reminds him of Simon. Since then, he's been looking to see who at school wears Elliott Smith shirts, even though he thinks it's unfair to try to figure out Simon's identity. Blue gives Simon a hint to his own identity: Blue’s dad is visiting from Savanna this weekend to celebrate Hanukkah with him at a hotel. Blue says he's considering coming out to his dad then.
By diving into Simon's music taste, Blue has the opportunity to get to know Simon on a much deeper level. Because one's musical tastes can be an extremely personal and intimate part of their identity, this again illustrates how the anonymity of email and not knowing each other in real life facilitates these deeper conversations and feelings. Coming out to his dad would mean a major change in Blue's family, showing that Simon's family isn't the only family in flux.
In Simon's reply, he is shocked to learn that Blue is Jewish and commends Blue for thinking about coming out. He asks how Blue thinks his parents will react. He then says that he doesn't wear band tee shirts, since he thinks people should have to go to shows in order to wear them, and he's not been to many shows. Blue writes back and says he's not technically Jewish, and Blue’s mom is Episcopalian. He says that both religions are supposedly friendly to gay people, but it's hard to tell if your own parents will be okay with it. He says that if he could, he'd buy Simon all the band tee shirts online, or they could just go to shows together.
Even though Simon later goes on to describe himself as staunchly nonreligious, it's telling that he never questions what Blue's religion might be. This shows that Simon is still very much tuned into himself and not necessarily into others, which in turn leaves him open to making misguided assumptions.