The changes to Shamanism and Flame Shock amount to a clear buff to PvE damage for Elemental Shaman. They still suffer from the major problems they've always suffered (very poor scaling with raid buffs, as well as Totem of Wrath's limitations - both that it sucks up a fire totem slot {not in bliz's stated immediate plans for correction} and that it does not always compare well to the spellpower buff provided by Demonology Warlocks {which bliz has stated that they intend to correct for 3.3 and icecrown raiding}), but a buff is a buff.

Interestingly, the standard Elemental rotation and spec changed, and now includes Chain Lightning even on single targets (it does more damage in its 1.5 second cast time than Lightning Bolt with its 2 second cast time). Whether it is used on-cooldown or directly after Lava Blasting (for the clearcasting mana reduction) is a matter of both choice the sustainability of the rotation. The standard spec for elementals no longer includes Elemental Warding for the reduced damage taken, but will include full Combustion for lower Chain Lightning mana costs.

Flame Shock changes mean the standard Glyphs for Elemental will be:

before 2t8: Flame Shock, Lightning Bolt, Totem of Wrath
with 2t8: Lightning Bolt, Totem of Wrath, Lava
post 2t8: Flame Shock, Lightning Bolt, Lava (under the assumption that shaman who replace all their t8 gear will have enough spellpower so that the improved scaling from Lava is greater than the flat bonus to spellpower from Glyph of ToWrath).