Are you getting this Ansible error message, even though you are damn sure boto is installed?
msg=’boto required for this module’
One possible reason for this is the message is referring to the status of the remote machine, not the machine that you are running Ansible from and you do not have boto installed on the remote machine. Doh!
Also, by default, Ansible uses the default python interpreter. This is probably not your virtualenv (if you use one). Boto needs to be installed for that interpreter. You can check to see if this is the problem, by SSH-ing to the remote machine and running:
sudo pip install boto