If you have loaded up World Wind since last night, you may noticed a new LandSat layer under your images section. The i-cubed Landsat was pushed out last night for all to use.
An Isilon cluster was used by i3 to optimally process the raw Landsat7 data using sophisticated i3 color-balancing algorithms. Isilon systems donated to NASA were again used to rapidly build the i3 donated color-balanced imagery into World Wind's tiling scheme. Much thanks goes to i3 and Isilon for their generosity of donating this imagery into the public domain.
Now, this server will be a little slow till a lot of the imagery is cached and you may find "black holes" of missing imagery. Try refreshing your cache (f5) of that location first. If it keeps showing up, post the error on the World Wind Forum and be sure to use the World Wind URL (Ctrl-C in World Wind) so the location can be found and verified broken / fixed.
old news