From the Los Angeles Times:

Demand for Fuel Seems to Be Falling

The Energy Department issues weekly reports on gasoline demand and supplies, and many analysts expected its newest report Thursday to show a surge in demand during the four days after Katrina's devastation, reflecting the panic buying.

Yet the agency's statistics arm, the Energy Information Administration, reported Thursday that in the week ended Sept. 2, gasoline demand fell 4% from the previous week to 9.03 million barrels a day.

The Energy Information Administration also said that for the four weeks ended Sept. 2, demand inched up only 0.1% from a year earlier to 9.33 million barrels a day, an increase well below the 1.2% to 1.6% year-over-year gains reported in late August.

Gasoline demand had lower growth, but it was still growth. That may change over next few weeks (its a 4 week average after all).

Also note in that same report that 21.5mm bbl/day total product demand was just a shade under the record high for year, set the week prior.

Even if demand growth slows dramatically, its still growth -- and supply of refined products will be down

No, consumption did not grow, it fell.  See http://www.eia.doe.gov/pub/oil_gas/petroleum/data_publications/weekly_petroleum_status_report/curren t/txt/wpsr.txt at the bottom under PRODUCT SUPPLIED, Finished Motor Gasoline. The previous week it was 9,406 thousand barrels/day and this week it was 9,027. That is the gasoline that is supplied to and used by customers. It represents an actual drop in consumption. The printed version of the L.A. Times had a graph which showed consumption levels and there was an obvious downturn.
I use the summary tables in the weekly report; near as I can tell, the summary table includes ethanol; the raw data below may not. For my purposes, total consumption of gasoline tells the trend story - I'm uninterested in minor variations when ethanol blending is removed from total.

As always, damned lies and statistics.

Summary table:
Finished Motor Gasoline (4)              9,328     9,316

Input table:
Finished Motor Gasoline                   9,408    9,471

4 Includes field production of fuel ethanol and an adjustment for motor
    gasoline blending components.

Does it matter much? Who knows. We will only know when several data points, not one. We also don't know how lack of availability of gasoline to purchase in some areas fits in with statistics. IF demand is there but not enough supply, prices will remain high even if apparent "demand" via what can be supplied... goes down.