I'm not so sure about this one, unless you count mind flay as a damage over time effect. The last time I played shadow priest (in Burning Crusade), VT and SWP were a huge portion of my damage, almost 40%. Now, they seem much weaker.
I guess it's just a preference thing, but I always thought shadow priest should feel more like an affliction warlock than a mage. Right now, however, most of your damage comes from the stuff you sit there and cast/channel. Really disappointed.