I wrote a long blog post on taxes that might be helpful. See:
http://www.crowdcrux.com/kickstarter-in ... lications/Basically, I found that you first need to classify the pledges into two types: donations and purchases of the product.
For the tiers where the backers are essentially buying swag or the product, you would then calculate your expenses and subtract them to get your taxable income.
Sales tax may apply if you meet the IRS requirements.
“The current default rule throughout the United States is that you must collect sales tax on Internet sales to customers in those states where your business has a ‘physical presence.’
I'm not an accountant or a lawyer, so I would highly recommend consulting both of them to be 100% certain. My articles/tips don't constitute legal or tax advice.