Tact, I was out on mine this evening and did notice some rattle in front, but it seemed to be originating up high and was probably associated with the gearshift linkage. It wasn't that loud, mind you, but it definitely was a rattle. It is not nearly enough to be objectionable. So if you can describe a little better whether it was a heavy metallic rattle or something much less like I've described, maybe we can compare notes.
One thing to consider here is that I recently tweaked my idle speed down (mine's an '05 where it came from the factory with a fairly high idle speed). As a result, the new lower speed probably matches the resonant frequency of some of the mechanicals. Again, it's not nearly loud enough to be objectionable to me.