3.3: How do you hide the new dashboard welcome panel?

If you’re using multisite, there’s a plugin you can network activate to disable the welcome panel on all new sites. It’s aptly named “Hide Welcome Panel for Multisite.”

If you just want to do this for a typical (single site) installation, it’s also pretty easy. The welcome screen is shown for a user if a specific meta key is set. So, add the following to a plugin and activate it …

add_action( 'load-index.php', 'hide_welcome_panel' );

function hide_welcome_panel() {
    $user_id = get_current_user_id();

    if ( 1 == get_user_meta( $user_id, 'show_welcome_panel', true ) )
        update_user_meta( $user_id, 'show_welcome_panel', 0 );
}

This code is adapted directly from the above-mentioned plugin, but I haven’t had a chance to personally test it …