Everywhere I look lately, I see cars with 13.1 stickers or, as I saw in the Y when taking my daughter to a swimming lesson, a “13.1 – half marathon, full race” sticker.
I'm not sure whether this is a fad or not, though. It's much easier to prepare for and do than a full marathon but it has that great “marathon” tag on it.
Honestly, for the well being of the once-and-done runners, I'm all for this movement. The marathon is hazardous for poorly prepared runners. The half is a distance where you can struggle through it and survive, almost regardless of what you've been doing.