Launch day for faster comms satellites

O3b space constellation to launch

http://www.bbc.co.uk/news/science-environment-23028083

Lower altitude satellites should mean lower latency compared to other satellites.

O3B (The other three Billion)

They are aiming at the most disadvantaged market to be found in satalite commuacations. Such long term investment is not often found in todays world. When the goal is hook-up for those most likely to be left behind. we can only thank them and wish them the best of luck!
(But how do they keep them from falling out of the sky at that elevation!?)

I'm not sure, but I suspect they're orbiting at a fast speed for this reason.

That sounds like the most likey answer. Thanks Danrok

Lower altitude means they are no longer geo-stationary. That means it is necessary to track the satellites and do signal handoff as they cross the horizon.

Not an insurmountable problem (cell phones do it all the time), but definitely a complication.

As to your question Daniel, yes they orbit at a higher velocity when they are closer to the earth.

Less time to duck when they come down! ":O}