Hi,

simple question - simple answer:

Pros: Increased Security. Any reasons to not keep the "bad guys" away from your virtual infrastructure?

Cons: Administrative effort also increases. Some things may not work as expected.

Imho it is worth to apply security hardening to the virtual infrastructure. But of course it depends on your security requirements (e.g. DMZ).

But remember, information security is not just a technical task - it is a process with lots of things to consider (e.g. password policies, roles and responsibilities, etc...)

Maybe this is a good starting point:

http://en.wikipedia.org/wiki/Information_security

http://www.vmware.com/technical-resources/security/index.html

http://blogs.vmware.com/security/

Cheers

David