The flavor depends on environment, much like rabbit. (if you've never eated a rabbit from sagebrush country out west, you should give it a shot...)
If it's been gnawing on moss off the bottom of a salty water source, they can get a bit 'alligator'ish - (read: fishy) - but the ones that have been munching on flowers and leaves tend to be VERY mild flavored.
As some folks have pointed out, there is always a concern with chemical ingestion from lawns and such, so, it's probably best to consider what they've been eating before you eat them, not just for flavor reasons.