the order of talent placement for my shamans is

5/5 concussion
5/5 convection
1/1 elemental focus
5/5 call of thunder
3/3 eye of storm
1/3 elemtnal warding
1/1 elemental fury
4/5 unrelenting storm
5/5 lightning mastry
1/1 elemental master
5/5 finish unrelenting storm
2/2 storm reach
one more pointing into elemntal warding (2/3)
5/5 lightning overload
1/1 totem of wrath
finish elemental warding (3/3)
5/5 imp healing wave
3/3 ancestral healing
2/5 tidal focus
5/5 healing focus
4/5 tidal mastery

the last point in elemental warding can go into tidal mastery instead if you want.
the difference between 41/0/20 and 40/0/21 is dropping totem of wrath for nature's swiftness. Wrath is very heavy PvE build though because insta-cast heals and bolts is hard to beat in PvP especially in arenas.