understanding pingbacks and xml-rpc

I picked a random blog from my multisite install, the theme seems to have the correct hooks set and in the source code of the page I do find:
<link rel="pingback" href="http://marius.zice.ro/xmlrpc.php" />

does this mean this blog can receive pingbacks? can it also send pingbacks to other blogs?

if I click that rpc link I get this feedback in my browser:

XML-RPC server accepts POST requests only.

is this ok? any configuration I am missing?
by default Atom Publishing Protocol and XML-RPC are disabled for new blogs but I thought that was only for users publishing remotely to their blog.
can someone enlighten me a little, please?