Brazil has made some headway in banning billboards in São Paulo and there is interest in Texas and California as well.
A Sign of Things to Come? - Advertising Age - News - read article
São Paulo made history by banning ads on billboards, neon signs and electronic panels, and now Rio de Janeiro is considering a similar measure. . . In the U.S., Vermont, Maine, Hawaii and Alaska all have long-standing policies forbidding outdoor ads, and legislators in Austin, Texas, and San Francisco have explored similar bans.