One of my biggest problems with almost every D&D version is the races. Why? They are generally bland, and can easily just be exchanged with humans of different cultures.
The first thing that made me happy about 4th edition was that the designers telling us that they saw that problem too. They have worked at solving it in three ways, as I see it:
1. Trying to find relevant and exciting racial abilities
2. Racial feats making it so that racial differences can keep growing over time
3. New and less human-like races
As it is now I like seven out of eight of the 4th edition races. (Somehow I even like halflings!) I still don't see the point of half-elves. I think mixed races are better built by starting with one race and adding a feat to give characteristics from the other one. With the addition of eladrins and tieflings, half-elves become even more pointless to me. How come there is a race based on interbreeding between humans and elves, but other races can't do it? I mean, elf/eladrin seems more likely than half-elf doesn't it? Or human/tiefling for that matter, considering the origin of the tiefling race.
I am also one of those who has read way more fantasy than any person ever should, and to me tieflings and eladrin are way more standard than halflings and gnomes. Dragonborn are a bit more out there, but not something I would have a problem with. I would like a good rebuild of werewolves, changelings, some sort of insect people and some type of undead, as those are extremely useful for different kinds of fantasy settings.
I personally loved one part in a game where I scared off enemies by singing the "Doom Song" but the echoes made it so far down the corridor it sounded like a demon 
