I've been spending a fair amount of time in California the last couple of years. Even though marijuana is only legal for medical use according to state law (still illegal by federal law) it is readily available to just about anyone. That being said I don't notice any great difference in the behavior of the people out there from the people around here. In my opinion the casual observer will probably not notice any major behavioral changes in public due to the legalization of marijuana for medical or casual use. Societal changes are another matter. Decriminalization will result in fewer people having their lives and that of their families disrupted by the legal system. Violent crime associated with the dealing of marijuana would probably disappear. Tax revenue would increase. I suspect that employers will still be able to restrict hiring and prohibit use by their employees.