Zogby predicted every 2006 Senate race correctly.
So did pretty much polling organization in the country. In many of the races, Zogby's margins were totally off (the Senate races in Ohio, Pennsylvania and Tennessee for example).
Besides, when the results of a race are going to be known to the world when it's over, it pays to do your damnedest to get it right. Not the case with this type of poll. There will never be any results to compare it to. It will never be judged for accuracy. It's just Zogby, an activist leftist, pushing his own leftist agenda. Like he does every other time he can get away with it.
Trust the guy at your peril. But I sure as hell don't.