I was especially disappointed after reading rmc's comment that "One of [OpenStreetMap's] statements is 'We make beautiful maps'".
It's great that the data is made public, and they play an important role there. But if we're only comparing map styles (as the article did), OSM has a long way to go.
Cloudmade's default rendering of New York looks pretty decent: http://maps.cloudmade.com/?lat=40.741014&lng=-74.009399&... but they also let you create your own style (e.g. http://maps.cloudmade.com/?lat=40.741014&lng=-74.009399&...)
Lars Ahlzen uses OSM data to make beautiful maps at http://toposm.com/
...the list goes on.