Thanks to this Atlantic Cities article, I recently learned that the FCC now publishes Census tract-level data on the ratio of "residential fixed broadband connections" (cable modem and DSL accounts) to households. The December 2012 data were posted on the FCC site in December 2013.
So here's what the digital divide looks like in Cuyahoga County.
And here's the city of Cleveland:
Looks a lot like this, doesn't it?
(See the CYC Project's Cuyahoga County Internet Survey for more information about who's connected and who's not.)