ODesk did absolutely nothing to earn it's cut.
ODesk had no monitoring system in place or any method to keep a contractor on their deadlines.
The only thing this site did was find me a poor contractor (who never finished to job) They do provide a very nice UI for me to pay them their money.
Never using this service again in my life! It's a shame too as I have many projects requiring contractors, just not a good service to use.