I was curious how new talent Echo of Elements behave, so I did some testing.
Testing was done with tauren shaman in enhancement spec (with three exceptions) wow beta build 15544 on training dummy lvl 85.
I found that following spells are duplicated:
Lightning bolt
Chain lightning (usually all three hits were duplicated, but sometimes only two of them)
Earth Shock
Frost Shock
Flame Shock (only initial damage)
Lava Burst
Unleash Flame
Healing Surge
Chain Heal (tried only on single target)
Healing Wave (in resto spec)
Riptide (in resto spec)
strangely i couldn't duplicate Unleash Frost and Greater Healing Wave (in resto spec).
Lightning Shield didn't proc, because ICD (I think).
I wasn't able to duplicate Lava Lash, Stormstrike, Unleash Wind and Searing Bolt as well.
I calculated rough proc chance from Lightning Bolt (80 casts) and Earth Shock (50 casts). It seems proc chance is about 36-38 % (very rough due to small sample).
Chain Lightning behaves quite strangely and definitelly requires more testing. From 10 casts i got 7 procs. Usually all three hits were duplicated, but sometimes i got only two more hits. I don't know if problem is in combatlog or in game itself.
Large part of test was recorded and you can see it
here