The latency would be ridiculous for most use cases.
Are you sure? A round-trip latency of 13ms to the base station(s) seems fairly reasonable to me. These are Low Earth Orbit satellites with an altitude between 99 and 1,200 miles, not geostationary ones at 22,236 miles; that's 1/18th the distance, and thus latency, of existing satellite Internet providers like WildBlue or HughesNet. At the minimum LEO altitude the latency would be another order of magnitude lower still (around 1ms). Even the high-LEO delay is significantly less than the 20-40ms time to the first router reported by traceroute for my Qwest DSL connection.
The trade-offs of LEO include a requirement for many more satellites for the same coverage, the necessity of hand-offs as the satellites pass overhead, and lower orbital lifetimes / higher fuel consumption due to increased atmospheric drag.