OpenStreetMap
I did some cleanup in OpenStreetMap, around the National Mall in DC. Some parks data from DCGIS had been imported, but there were duplicates with what was already in OSM. In looking at the map after my cleanup, I noticed something quite odd. "Vietnam Memorial" is written with the "memorial" part upside down. I didn't realize that Mapnik writes labels upside down.
In edit mode, I saw that the Vietnam Memorial was drawn as a polygon and tagged with just a name. Also, the Constitution Avenue label is cut off and shows it as just "Constitu". I went in and tagged the Vietnam Memorial as tourism=attraction and historic=memorial. Now it renders as an area and seems labeled properly, offset from the polygon and right side up.
Though I am not sure the walkways are correct and need to check them with a visit. There is plenty more to do with both data imports and collecting details around the mall.
Discussion
Comment from davespod on 11 December 2009 at 10:23
Looks like you've fixed the upside down text - was it an unclosed way? I've had similar effects when I have thought I have closed a way, but have not. The cut-off name will be due to some of the tiles rerendering but not others. It is probably that the traffic lights have been added, and the tiles in which they appear have been rerendered, but not the adjacent tiles. It will probably rerender eventually, but if it is bothering you, you can, right click to find the URL of the tile, then load the tile on its own in another browser window, with the suffix:
/dirty
The tile will then be submitted for rerendering. In this case, it will probably cause the label to disappear, as there may not be room between the traffic lights. It will probably reappear on a stretch of the way with fewer obstacles.