I *really* liked the art for the healer... I think it's the best class art I've seen yet, hands down.
As for the class itself...
I think the "girlfriend" analogy is a pretty good one, and the class does seem to be marketed that way (unicorn being the obvious example). I would have liked to see the class have something else instead - there are far too many classes that grant some sort of special animal/mount that it's getting old.
I also would have loved to have seen a class that heals without casting spells. I think a healing class with no spells would have been a lot more interesting than something that really has the cleric's spell list with a lot dropped out. As an example, the dragon shaman is almost a cleric replacement, and he gets no spells whatsoever... doing something similar with the healer would have been great.
I also think the healer's ability to regenerate limbs for characters is neat, but outside of the scope of the D&D rules. I don't know about you, but we didn't have too many characters losing limbs, and, to the best of my knowledge, there isn't a whole lot in the rules that could cause a character to lose a limb (except for vorpal weapons, but a head isn't really a "limb", y'know?). So, it seems silly to allow a character to fix a problem that isn't ever really a problem addressed in the rules.
As in, if you play the game by the rules, it's highly unlikely your character will lose a limb in combat. Because of this, it's highly unlikely that a healer will ever use the restore limb ability. But, whatever.
If you were to try and play a healer in my campaign, I'd probably refer you to a cleric with the healing domain... but that's because I play in smaller groups where the highly-specialized nature of the healer would be detrimental to the group as a whole. If I were running a larger party (say, six or seven players with henchmen), then I'd be all for a player running a healer. Even then, I'd allow the healer a speed boost (to better move about the battlefield), a choice of animal companions, and maybe an expanded spell list.