vCenter and associated components focus on management of virtual infrastructure - physical (non-virtualized) infrastructure will typically require separate management.
However, one can argue that there are increasingly aspects of physical management (bare metal host deploy, vCenter Operations capabilities, vCenter monitoring of physical hosts etc. but the core focusses on the virtual aspects).
Additionally, VMware encourages 3rd party vendors to provide management plug-ins for the vCenter Client (classic or web) that can manage peripheral components of the environment (3rd party storage, servers etc.).
Example for plugin guidelines here: http://bit.ly/17wF0RH