This is a nitpick, but for commercial (civil aviation) use (unless you are contracting to a government agency) you need a special airworthiness certificate (SAW). Certificates of authorization (COA) are for government use (public aviation). This matters if you want to do commercial operations because COAs and SAWs are issued by different parts of the FAA, and are evaluated differently. I'm not aware of anyone who's gotten a SAW yet.
Hopefully this will change for the better when SFAR part 107 comes out.
This may get better.
From an FAA commentary on COAs and SACs:
"However, this clarification also advised the public that the FAA
would evaluate alternatives to authorize certain kinds of sUAS
operations without the above restrictions. This evaluation of
alternatives resulted in the FAA establishing an Aviation
Rulemaking Committee (ARC) comprised of members from the
sUAS industry, operators, aviation associations, and other
According to the US DOT the NPRM is due in March 2011.