I'm confused.  Becker shows $100 but Wiley is showing $500----  both before the 10% AGI limit.

Can anyone clear this up?

Got the answer at: http://www.irs.gov/pub/irs-pdf/f4684.pdf

"The amount of the loss for personal use property must be further reduced by a $100 ($500 for 2009) per event floor and a 10% of AGI aggregate floor. The $100 ($500) floor applies separately to each casualty and applies to the entire loss from each casualty [ex. if a storm damages both a taxpayer's residence and automobile, only $100 ($500) is subtracted from the total amount of the loss]. The losses are then added together, and the total is reduced by 10% of the taxpayer's AGI. The resulting loss is the taxpayer's itemized deduction for casualty and theft losses."

From the 2011 edition of the South-Western Federal Taxation textbook