This new article explains more about elves, eladrin and drow in 4e.
I was originally apprehensive about the changes to Eladrin, when it seemed that they were turning them into Grey Elves. But now it's getting to be more preferable to me.
They've bothered to make Eladrin, Elves and Drow into fey, as they were once one race that lived in the Faerie Realm/Feywild. And at least with them their emphasizing that part of those races. But what I found that with all the changes to Eladrin that they've been doing making them into a PC race in the Player's Handbook, is the mention of the subraces of Eladrin. Though now they're described as Eladrin Nobles, of certain houses associated with seasons and emotions.
The Ghaele have been cast as the house of winter, Bralani as autumn, Coure possibly with strife and mischief and Firre as the house of passion. It at least builds off the theories others around here have had in the past about the Eladrin, despite all the drastic changes they've been doing to them.
On an amusing note, it mentions that some elves worship Gruumsh.