First off, this is not a new law or change in the law to be "passed"...that is done by congress. This is the Supreme Court hearing oral arguments in the case of Kirtsaeng v John Wiley & Sons whereby John Wiley & Sons sued Kirtsaeng for copyright infringement. This is not big business and coorporate entities trying to influence Congress, etc.
Basically, Kirtsaeng, a Thai imigrant, purchased text books in Thailand when going to college in the US. Only, he wasn't purchasing the text books for himself...he was purchasing them at a substantially lower cost than purchasing in the US for the sole purpose of resale, generating upwards of $1.2M. John Wiley & Sons have thusfar, successfully argued that the first-sale-doctrine (Kirtsaeng's defense) doesn't apply in this matter in that, basically, Kirtsaeng made himself a "black market" vendor, and un-authorized/un-licensed vendor of their text books.
I wouldn't be surprised at all if the Supreme Court rules with the lower courts in this matter. Implications are pretty big, especially for folks who like to buy stuff really cheap oversees and then flip it. Personally, I don't think it will be that big of a deal for the re-sale of "used" goods as it would be next to impossible to police and economically, wouldn't really be worth these companies coming after someone. It's a whole other story when you're acting as "vendor" without a license and agreement with the copywriter.
It would also appear that, should the SC uphold the lower court's rulings, that the congress would step in to amend language to existing laws to protect a persons rights to sell their used goods...would have stipulations regarding buying in bulk for the sole purpose of re-sale.