Patch 6.0.2 (14-October-2014): Totems will no longer cause hostile creatures to enter combat with the Shaman based on proximity.
Patch 5.1.0 (27-Nov-2012): All totems are now considered spells, and summoning totems can be prevented by silencing effects. Searing Totem, Magma Totem, and Fire Elemental totems fall into the Fire school, while all other totems fall under the Nature school.
Patch 4.0.6 (8-Feb-2011): Tremor Totem has been redesigned. The totem is now usable under Fear, Charm, or Sleep effects, and pulses much more rapidly, but lasts 6 seconds and has a 1-minute cooldown.
Patch 3.1.0 (14-Apr-2009): Now correctly pulses every 3 seconds, up from 1 second.
Patch 3.0.8 (2009-01-20): Tremor Totem's duration has been increased from 2 minutes to 5 minutes.
/Patch 3.0.2 (14-Oct-2008): All totems are now considered on the "Physical" school, and no longer magical spells.
Patch 2.4.0 (25-Mar-2008): Tremor Totem now pulses every 3 seconds, down from 4 seconds.