So, I found some time to re-test this evening.

The following is accurate as of 3.2.2 (2nd October 2009):

It is NOT POSSIBLE to sap somebody in Ghost Wolf - the rogue gets "Invalid target".

Fire Nova totem, Magma Totem and Thunderstorm all BREAK STEALTH.

Searing Totem doesn't any longer, and nor does Stoneclaw.

For completeness, I also tested with Earthbind and although the stealthed rogue / druid (I tried with both) gets the slowing effect, they appear to be immune to the root effect and it doesn't break stealth.

It's a shame about Searing Totem, because it lasted the longest and had the longest range. That was probably the problem of course - cheap, long lasting and long range probably = overpowered.

I forsee my guys all huddled around their 8 yard Magma Totems!