Stop 1 · Watch
Every source gets its own watcher
Rather than one clever scraper, each community page and site runs as its own scheduled Make scenario.
City government, the school district, the chamber of commerce, the public library, parks and recreation, theatres, sports clubs, local businesses and event calendars each have a scenario of their own. Facebook pages use the Watch Posts module; websites are fetched over HTTP and parsed out of the raw HTML. Each one runs on its own schedule and returns only what has appeared since it last looked.
One scenario per source is deliberately the unglamorous choice. A single generic scraper breaks the first time one site changes its markup, and takes every other source down with it.