I tend to agree with Atrios: despite Instapundit's apparent support, I remain somewhat unimpressed with http://www.mediawhoresonlinewatch. So far, the new MWO watchblog usually 'refutes' the liberal talking points that MWO brings up with conservative/libertarian talking points of their own. It helps that MWOwatch benefits from the echo chamber's support, but I don't see them dragging down the popularity of MWO any time soon. They also seem oddly inconsistent: sometimes they argue that they are correcting MWO's falsehoods, sometimes they argue that they are simply writing "a conservative response", and sometimes can't seem to decide between the two. At best, I imagine they'll just be a tool for conservative pundits and bloggers to use when MWO cuts a little too deeply.
Besides, the obvious point remains: if MWO were so inaccurate, partisan, and unimportant, why would it warrant a watchblog?