Another announce from MapQuest:

"currently offers global imagery at a 30-meter resolution and up to 1-meter for the United States. The service itself is still very much in its early stages as we continue to augment the initial dataset with more and improved data.

However, if you’d like to begin using the Open Aerial Tiles now or in the early stages, the process is very similar to using OpenStreetMap tiles. The only change needed would be the tile URLs."

OpenStreetMap Tile URL: http://a.tile.openstreetmap.org/8/126/87.png
MapQuest-OSM Tile URL: http://otile1.mqcdn.com/tiles/1.0.0/osm/8/126/87.png
MapQuest-Open Aerial Tiles URL: http://oatile1.mqcdn.com/naip/8/126/87.png