The "do_action"s in class-wp-xmlrpc-server.php do not pass in useable arguments.

[jtsternberg]

It seems it should be possible to use hooks like do_action( 'xmlrpc_call', 'wp.newPost' ); to manipulate xmlrpc-inserted posts, terms, etc.

These would be infinitely more useable.
do_action( 'xmlrpc_call', 'wp.newPost', $user, $content_struct );
do_action( 'xmlrpc_call', 'wp.editPost', $blog_id, $user, $post_id, $content_struct );
do_action( 'xmlrpc_call', 'wp.newTerm', $user, $content_struct );

[maxcutler]

XML-RPC uses wp_insert_post internally, so you can use the usual 'save_post' action to do work after it has been saved.

Or if you want to manipulate it before it is saved, look at the 'xmlrpc_prepare_post' filter.

[nacin]

The only purpose of the xmlrpc_call actions is to announce that a method is being used. As maxcutler says, there are other ways.

[Viruthagiri]

Replying to maxcutler:

XML-RPC uses wp_insert_post internally, so you can use the usual 'save_post' action to do work after it has been saved.

Or if you want to manipulate it before it is saved, look at the 'xmlrpc_prepare_post' filter.

'wp_insert_post' hooks are not useful here. Because XML-RPC uses 'get_default_post_to_edit' first.