Short version: it's a podcast that purports to be a newscast from the fictional desert town of Night Vale, where the weird and uncanny exist side-to-side with the residents. It's horror-like, but not especially scary. As someone else said, give it a few episodes: if I'd just listeend to the first, I'd have been thrown off by the narrator's voice as I felt--at frist--that it would ahve worked better with a more news-reporter sound instead of the Storytelling Voice that he employs, but within a few episodes they develop the character of the narrator, so he becomes Cecil, the news reporter at the community radio station, and I forgive him the voice because it's a community radio station and not, say, NPR. :D
kate_nepveu has a good, nonspoilery intro to the show.
You can comment here or at the Dreamwidth crosspost. comments at Dreamwidth.