Since the information on the website is somewhat outdated and such, I'm creating this thread to help teach you everything you may want to know about the mechanics
10:14 : Fire Genasi: +2 Int, 50% Fire Resist, +1 taunt, +1 concentration, +2 will. Form Flame Ability : Combust / or Create a flame /day ability.
10:15 : Water Genasi: +2 Constitution, 25% Cold Resist, +1 tumble, +1 reflex. Water Leap Ability : Can teleport a short distance in water. Immunity to Drown, Unlimited Underwater Breathing.
10:15 : Earth Genasi: +2 Strength, +2 Constitution, -2 Wisdom, -2 Dexterity, +2 Discipline,
10:15 : Air Genasi: +2 Dexterity, +2 Intelligence, -2 Wisdom, -2 Strength, +3 Move Silently, +3 Tumble. Mist Shape : Can turn into a breeze for a short moment (6 seconds) -- a lesser form of Mist form.
10:15 : Tree Genasi: +2 Constitution, +2 Natural AC, (+4 Hide / +4 MS in Forests), 25% Fire Vulnerability, Tree Stride : Ability to Teleport from Tree to Tree on a short distance.
The special abilities may not all be working appropriate but this is an up to date list as provided by Howland.
More information may be found here, under the Realmslore file then "Uncommon Folk of Faerun on Planetouched (http://www.escapefromundeath.com/forums/showthread.php?t=672) individuals.