I agree completely. Worldview 3 is the current satellite that has the capacity of 680000KM2 per day of capture. However there are some fairly significant shortcomings of utilising satellites for this purpose.
http://www.satimagingcorp.com/satellite-sensors/worldview-3/
Worldview 3 has a storage capacity of 2.2TB. The max communications speed of the satellite is 1200Mbps. At those speeds it would take 31 minutes to upload a single hard drive worth of data. These would be
optimum speeds and would likely only be achievable when overhead the receiver, and not continuous uploads as the capture is taking place.
Assuming that the 680000 capacity is achievable at 30cm resolution (which i don't believe it is, based on the spec sheet), at 11 bits per pixel, this theoretical capacity would generate a minimum 77403GB of data. That is 35 hard disks worth of of data, and 18.34 hours worth of continuous upload time.
This would mean that the theoretical capacity and the actual capacity are substantially different, given that the satellite would likely have to perform 35 uploads a day at 31 minutes an upload to capture the theoretical maximum.
This presents an even bigger problem if the satellite attempts to get to 10cm or lower resolution.
at 10cm the idea of capturing that much information is ridiculous. at 696629GB, and 316 hard drives worth of data, the theoretical capacity is entirely impossible. It would take 165 hours to upload the data, so more realistically a single hard drive could hold 2147 sqkm of data. and only 193 sqkm at 3cm.
at 10cm, capture of the entire US would require 4577 hard drives worth of data, and require 2365 hours (98 days) to upload.
Even if you were to generously assume that the satellite was able to upload continuously while taking these photos, the turnaround time will never be as low as nearmap. Higher tech doesn't always improve efficiency or costs. Nearmap has a competitive advantage being smaller, lower tech and much lower fixed costs enabling them to provide a better, more scaleable service to their clients. They can send multiple planes if requests coverage requests increase, something that cannot be achieved easily with satellite coverage.
