There is a Survey USA poll also showing a big lead for Arnold (52-38), including breaking even with the Hispanic vote, getting a third of the black vote, carrying the Asian vote with a substantial plurality (albeit with a high undecided factor), and even breaking even in the Bay area, while carrying LA county handsomely. The one odd thing is that Arnold is doing horribly with young people (gen Y), per the crosstabs. If they are the future in California, it ain't pretty.
I might add that I have seen a lot of polls a lot of places, and the GOP is doing better north of the Mason Dixon line with blacks in most places than the normal partisan baseline. One can speculate why, but it is there.