Vault.com has an excellent article "The Change in LSAT Reporting Requirements and YOU?" In a nutshell, the ABA is asking schools to report the highest LSAT score of accepted students, not the average LSAT as in the past.
Vault believes, and I agree, that schools will begin reporting to US News the highest LSAT scores as a result of the ABA change. Check with the schools you are applying to about their policy towards multiple LSAT scores. I agree with Vault that the highest score will become more the norm as the score used in admissions decisions. And that’s an important change.
I also agree with Daniel Solove of Concurring Opinions that this would be a "terrific policy change." It would allow your best test score to count, not some numerical and in some way arbitrary average. For better or worse, it will also probably result in more applicants taking the LSAT multiple times.