Of course it's fanservice. The whole series is fanservice! Sugisaki's serious manga is Candidate for Goddess, as near as I can tell. DNAngel is just cuteness. Emiko speaks for fangirls everywhere when she dresses Dark like a J-rocker, after all. It's not quite as fourth-wall-breaking with commentary on the fanservice as, say, Koko wa Greenwood, where Mitsuru and Shinobu will actually crack wise about it just to see Hasukawa pop a sprocket in the cafeteria -- but it is, nevertheless, loaded down with fanservice-y things.

What I do find interesting about DNAngel, though, is the way the random slashiness is handled. Daisuke does not have the traditional response to getting pinned to a wall, which is, "ZOMG! Another boy touched me! AM I GAY? WHAT DO I DO!?" He's either totally oblivious, or completely aware of what is going on and doesn't mind, I can't decide which. Totally different from the usual social model, and thankfully less dripping with Angst.