This question has been revised & clarified significantly since the original version.
If we look at each trusted certificate in my Trusted Root store, how much should I trust them?
What factors should be taken into consideration when I evaluate the trust of each Root CA for potential removal from my local store?
If a CA issues a certificate to an improperly validated party, then that causes all machines that trust that CA vulnerable to MITM attacks. As a result all CA's stringently validate the requester of a given SSL certificate request to ensure the integrity of their CS chain.
However, a large part of this CA verification process is subject to human intervention and provides opportunities to issue a cert to the wrong party. This may be done by CA operator error, government demands, or perhaps the coercion (bribe) of a CA operator.
I'd like to learn more about which default CA's are more likely to issue certificates to the wrong party. I intend to use this information to advise users to remove that CA from their Trusted Cert Store
Suppose the government controlling a particular CA wants to assume the identity of Microsoft.com, and demands an exception to the CA's verification process. That government then also requires the secrecy of this exception be maintained. The generated key pair would then be used in a MITM attack.
Windows Azure Default Trust
Windows Azure supports 275 CA's as shown in the following link. Depending on the use of the particular CA, some of those CA's may increase the surface area of a particular attack. In fact this may be technically required to make some applications work correctly.
Amazon Default Trust
(not available) Please share links to Amazon, Google, and VMWare's default CA list if you come across them.
A list of all certificates and audit statements is available.
List of all iPhone root certificates