in PvE, i run only one shaman in my team, and rarely use it, as cleansing totem prevents more damage than healing totem would produce. It should probably scale a bit better with gear, as currently, with the kind of health pools most toons have these days, a couple hundred healing every 2 seconds is hardly worth it. I still use 4-5 of em in PvP though, as it does start to add up once they are stacked. Still, its losing its usefulness as we get geared up.