What about the Quill ruling? It's the law of the land -- but it's out of date. The world changed in 1994. Tax law should change with it. California should expect to be sued, and should expect to make its case to the Supreme Court that the Web gives a seller an actual presence in the state in a way that a mail-order catalog does not.
We sympathize with innovative online California businesses that were about to be cut off by Overstock, just as we sympathize with brick-and-mortar businesses that are being undersold by companies that don't add sales taxes. And we sympathize with California shoppers who don't really want to be tax deadbeats but are unaware that they owe use taxes on items they buy online from out-of-state sellers. For those sellers, though, it's another story. They claim that it would be unfair to burden them with the chore of calculating sales taxes for each of the taxing jurisdictions in which they sell. Nonsense. It would take a little programming, and they'd be set. We strongly suspect that their real objection is that they don't want to lose the unfair advantage of pretending their products are tax-free.