It looks like the SSL certificate on the update server was renewed yesterday and replaced with a certificate which is only valid starting yesterday:
Issued To
Common Name (CN) *.vmware.com
Organization (O) VMware
Organizational Unit (OU) IT Operations
[...]
Validity
Issued on 03/02/2013
Expires on 03/02/2014
If your system's clock is running behind (or if we deployed the new certificate too early!), there will be a transitory period in which certificate validation will fail because your machine thinks the certificate shouldn't be valid yet. I don't know how time zones work for certificate validation, but maybe if your time zone is set incorrectly it could fail too (even if your clock shows the right time!). So perhaps check your host's timezone, date and time.
Cheers,
--
Darius