Excellent post. Zogby is not a pollster, but a spinner. The problem with the vast lack of poll comprehension (thank you, public schools) by the body politic is that, in turn, spinners like Zogby can bury the garbage stink sauce in the MOE. After blowing the 2002 Congressional races, Bush's +4% / +290 EV win in 2004 will once and for all fully discredit Zogby and his methods.
All you need to know about Ziggy's credibility is this: He is an Arab, a Muslim exteremist dressed in western garb and a left wing liberal zealot.