The "multiple modes" problem is exactly what I always thought would make a bike mapping application really useful: if I could ask it to optimize for distance, or for hills, or for quality of ride.... or even scenery.

The route it recommends between East Arlington and my office favors the Minuteman bikeway extension all the way through Davis Square. That's a fine way to go if your goal is to minimize road travel, but I prefer taking Mass Ave. to Beacon St. and cutting a half-mile off the route. That's hard to account for, given the range of individual tastes.