baltimore aureole:

its kind of depressing that a young teen is looking forward to her first vibrator, rather than her first legitimate boyfriend.

As opposed to her first illegitimate boyfriend? I fail to see why this is depressing. Having been a 16 year old girl myself, I can remember how annoying most 16 year old boys were and yet meeting older guys was off limits.

baltimore aureole:

and when you sum it up this way, does that increase the odds that this might even be a "fake" letter?

I don't think so. You must not read Dan Savage's column. Believe me, there are plenty of teens who have started thinking about sex toys.