Like or As

I've often grumbled to myself that talking about metaphors vs. similes is not a distinction worth making -- a simile is just a metaphor where the comparison is made slightly more explicit by the presence of "like" or "as." But this sentence in a New York Times article about Maurice Sendak drives home the difference in how they can hit you:

Mr. Sendak, a square-shaped gnome, was sitting in the dining room of his Connecticut retreat.

The normal, newspaperly way to deliver that bit of color would be to say, "Mr. Sendak, looking like a square-shaped gnome, was sitting..." Okay, it's sort of an unusual line anyway, but it's a lot more striking without the "like."