I've been mapping for quite some time, spending a lot of resources getting a ridiculous amount of detail in the neighborhood I work. That work is 99% done, and I think I've got a pretty good sense of mapping for OSM.
Yesterday I started working on combing through Tallahassee via the Bing Satellite imagery and fixing things up. There's a lot of residential roads grossly misplaced, and dual carriageways that need to be split out as such.
My plan of attack is to make sure the major roads in Tallahassee are accurately mapped so that at the very least, routing applications could properly take people through the major parts of Tallahassee properly.
I'm debating spending resources on also marking POIs, such as gas stations and grocery stores. That is, of course, very nice to have, but could take significant time away from getting the streets down correctly.