Sounds like many of you yearn for the original Planescape tiefling, not necessarily but often evil because of a fiendish heritage, with a sort of aura about them that hints at their background.
I liked the original tiefling myself, but the 4e flavor that I've seen seems a bit boring. I'll just go back and dip into the original.
For eladrin, they'll just be the old grey/high elves renamed, big deal.