If you're looking for new material on genasi and run Dark Sun, this article has a healthy mix of flavor and crunch material for you.
There's a little more than four pages of information on history, role-playing, physical qualities, communities, personality traits, and backgrounds. I found it interesting, especially the bits on primordials creating the genasi themselves to help shape the world and fight the gods, before they retreated into a deep slumber. Unfortunately rather than protected the world as the primordials had hoped, they just ended up fighting each other until the other mortal races managed to get a numbers advantage. Then, to make matters worse, the sorcerer-kings managed to drain most of the life out of the world. So...yeah. They'd better hope that the primordials don't wake up, cause I don't think they'll just slap their children on the wrist.
Anyway, I like that it just comes out and explains some things, which is great for providing a prospecting DM with some solid history to go off of, as keeping the past undefined can be just as limiting for world-building. I also like that genasi aren't exactly painted in a good light: they don't seem to particularly like the mortal races, what with the whole killing the planet with life-draining magic, so they could make great villains. Unfortunately, this kind of limits the backstories that would easily allow integration into a party. I suppose since they seem to hate defliers and sorcerer-kings more than about anything else, you could always fall back to that...assuming that's the aim of your campaign.
On the crunchy side of things, there's four new elemental manifestations: embersoul, magmasoul, sandsoul, and sunsoul.
- Embersoul: You gain a bonus to Reflex and to saves against ongoing fire damage. You also gain ashfall evasion, which lets you explode into a zone of ashes that removes you from play and deals damage to enemies that end their turn there.
- Magmasoul: You gain a bonus to Fortitude, and when you take fire damage, you deal bonus fire damage. You gain flowing magma, which turns you into a being of, well, magma. You can't be subjected to forced movement, are slowed, and deal automatic damage to creatures that end their turn next to you.
- Sandsoul: You gain a bonus to Athletics and Acrobatics and a bonus against conditions that hamper your movement. You also gain sandslide, which makes you insubstantial and lets you move through enemies squares, as well as go through any opening larger than a grain of sand. Very cool.
- Sunsoul: You gain a bonus to saves against ongoing damage based around fire or radiant, and you don't suffer any problems in the temperature extremes (including sun sickness). Finally, you gain sun flare, which is an AoE that triggers when you're bloodied, causing you to make an attack that imposes attack penalties to creatures you hit (unless they are bloodied, in which case they are blinded instead). It also deals fire AND radiant damage, limiting resistances. My favorite out of the bunch.
The desert voice paragon path offers a lot of flexibility. The level 11 class features allow you to shift whenever you crit with a totem, gain a new manifestation from the ones in the article, and can deafen and slide creatures close to you when you burn an Action Point. The level 16 one provides a boost to any manifestations that you have, from increasing the range, to preventing creatures from standing up, to dealing automatic damage.
- The level 11 power is a close blast 5 that deals damage, pushes targets you hit, and imposes an attack penalty for a turn.
- The level 12 utility grants temp hps and recharges one of your elemental manifestations.
- The level 20 attack is a nice area burst that creatures a zone and deals automatic damage to creatures caught in it. You can also sustain it and make an attack that slows and deals ongoing damage to creatures inside it. It's nice that you can maintain it on the off chance that creatures get knocked back in, but you can't move it at all, so that kinda sucks.
The crunch works in any setting, and is really cool for genasi players. The fluff is intended for Dark Sun, but I could see the creation myth being used in any campaign setting. It's certainly better than the varied, vague ideas pitched in past Winning/Playing Race articles. It's also good for DMs looking for a solid Athasian villain.