From the article:
The maximum amount of marijuana for "personal use" under the new law is 5 grams—the equivalent of about four joints. The limit is a half gram for cocaine, the equivalent of about 4 "lines." For other drugs, the limits are 50 milligrams of heroin, 40 milligrams for methamphetamine and 0.015 milligrams for LSD.
I predict a new kind of tourist trap just across the border.