No, I haven’t seen or heard anything, and I hesitate to start defining him by personality type. All we really have to go off of are a myriad of public personas and lyrics. While lyrics are a good starting point, they’re not definitive enough proof of who he is. Even the most autobiographical works have a tendency to hyperbolize the writer, making he or she seem a certain way depending on the writer’s choice that day/month/year (for example: Moveable Feast). So, as cool as this concept is, I would hate for anyone to misconstrue the real Davey Havok based on lyrics/public personality.
But really cool question! I can do some more research on it for you.
My therapist did a Myers-Briggs for me once, but I forget what it was. I wasn’t particularly into it, LOL. Shocking because psychology was my minor in college.