the chargeback situation is getting worse and worse for merchants every day. People are figuring out that you can, in fact, go on a big shopping spree and then charge it all back. If you consider the incentive structure involved, you can see that it is likely to only get worse
Yup. Right now the cost of chargeback fraud is being assessed to the unfortunate merchant targeted by the scammer (as the merchant pays a fee that is over and above the return of the funds to the customer). But the costs of this fraud (PhD's employed by Visa and Mastercard writing scam-detection algorithms are expensive) are also subsidized by all the merchants together too -- currently about 3% for most retail.
But as Bitcoin and other cash payment methods (e.g., Dwolla) take share, the fraudsters will continue using payment cards with the chargeback option -- thus making it so the payment networks need to bump up their rates as a response. And that forces the remaining merchants to further press their customers to pay with Bitcoin or other cash methods, and so on ... resulting in the payment networks forced out of the market for their most profitable transactions.