I have pre-ordered mine but because I'm on T-Mobile's Jump On Demand program, so no reason not to, really. BUT if you're an ex-Note 7 user, the best deal is from Samsung, where you get 425 dollars off the Note 8 while trading in your S8. Unfortunately, that's not the best thing to do, though, since you can get the same amount off by trading in an older device down to a Galaxy S5. That's nearly as good as a BOGO promo, since you get the device for a final price of 550 (with taxes, so if you live in a non-taxable city, you get it for less) instead of the full retail price of 1,000 (that's with taxes). Downside is you need a trade-in for that.
The second 'best' deal I've heard of is from Verizon, where you get 480 dollars in bill credits (but you pay more for the device since Verizon charges the taxes on the full price because you're not getting a discount, you're getting bill credits, whereas Samsung charges only for the discounted final price). You also need a trade-in for that, if I'm not mistaken.
The other deal, but not as good, is Best Buy's, where you get 150 dollars off, but with no trade-in.