Amazon has their pre-order price guarantee, so that if you pre-order now and the price goes down, they’ll charge you the lower price or refund the difference.
And B&N gives free shipping with no minimums to members.
If you’d rather order from Powell’s or BAM or elsewhere, stay tuned. I’ll post links when I have them. Ditto the e-book formats. Heavy Metal will be available in stores on August 27.