The residual vote rate in AZ has dropped, based on unofficial election returns. The estimated rate for 2008 was 1.1%, compared to 1.3% in 2004 and 1.7% in 2000. Write-ins have yet to be recorded, which will reduce the residual vote rate even further.
Turnout also dropped a small amount, from 2,038,069 to 2,034,276. (The write-ins will perhaps pull the two years even.)
Coupled with the puzzling turnout situation in Alaska, Arizona reminds us that increases in turnout are usually generated by the mobilization activities of candidates. Having a favorite son (or daughter) on the ballot is not sufficient to excite the marginal voter to turn out at the polls.