Banning e-cigs

Why not encourage them, as a harm-reducing alternative to conventional smoking?

The Los Angeles City Council just voted for a complete ban on e-cigarettes wherever real cigarettes are banned, including parks, beaches, and bars. (UCLA adopted a similar policy campus-wide a few months ago.) Seems to me like a bizarre choice, and likely to retard the movement from cancer sticks to e-cigs that, if not interrupted, might save hundreds of thousands of lives per year. This morning on KPCC I debated the issue with a member of the city council majority.