No. They should have treated this question with deference to the US Constitution, specifically the Commerce Clause.
While the States might theoretically be short-changed on sales-tax collections due to internet shopping (a) you can't "lose" revenue you never had; (b) the obligation to pay the sales taxes was already in place, and it belonged to the consumer. The Supremes should have sent South Dakota back home and told them if they want their tax revenue, then go enforce the existing, Constitutional law against their own citizens. To do otherwise, clearly places a significant burden on the conduct of interstate commerce by forcing out-of-state merchants to be their toll collectors.
South Dakota may pass a law that forces out-of-state businesses to be its tax collectors, but what recourse do they have if you simply don't pay? It would probably cost more to enforce this type of arrangement than they'd ever raise in tax revenue.
You don't get it...do you?...Thats the idea!!!!!!!!