(Psi)SeveredHead
Adventurer
They are elves. 4E took the five classic elf subraces--high, grey, wild, wood, and dark--and turned them into three distinct races. High and grey elves merged into eladrin; wild and wood elves merged into 4E-elves; dark elves became (remained) drow.
Since the dawn of D&D, elves had two conflicting identities:
- "Sylvan" elves, who were good with bows and wise in the ways of nature. This image stems from Legolas, the archetypcal elf in Lord of the Rings.
- "High" elves, who were chaotic and excelled with magic and sword. This image comes from Poul Anderson's stories, including Three Hearts & Three Lions and The Broken Sword.
Gygax was a fan of the second type of elf, but D&D players were fans of the first type. Over the years, many elf "subraces" cropped up to cover these: high elves, gray elves (Galadriel-inspired, perhaps?), wood elves, wild elves, etc.
When 4e rolled out, it was decided to make the distinction clearer and, in order to avoid "subraces", the "high" and "grey" elves became the eladrin.
Correct. I would have preferred only one kind of elf, but splitting elves this way makes elven "subtypes" irrelevant and the game less confusing.
Want to play a star elf? Play an eladrin. I think they can get +2 Charisma as one of their stat options. You don't need yet another subrace

I've never used eladrin in 3.x, even though they looked a little interesting, so to me removing eladrins as a planar race isn't a big deal. I suspect for any sort of converted plane-hopping campaign, some changes need to be made, one way or another.