Nationally dead on, but they flail around like crazy in state by state polling, You can check RCP,
Here's another example,
http://www.realclearpolitics.com/epolls/2008/president/nv/nevada_mccain_vs_obama-252.html
8 points off in Nevada? Their polling isn't just wrong, it's consistently wrong in one direction.
not sure if I made it clear, nationally they were GREAT, but state by state? at least 2 points towards mcCain in every single swing state, in many states closer to 4-5, and few more even worse.
Nationally their results seem good, but in states, it's Zogby level bad, with a dash of republican bias.
EDIT: Surprisingly, ARG looks pretty good in all these, what's the complain on ARG again?