Display Post Format as a String

Question

Try:

<?php
echo get_post_format_string( get_post_format() );
?>

EDIT

Note, if you want a fail-safe output, try this:

<?php
if ( get_post_format() ) {
    echo get_post_format_string( get_post_format() );
} else {
    ehco 'Standard';
}
?>

Or, if you want to store it in a variable:

<?php
$post_format_string = ( get_post_format() ? get_post_format_string( get_post_format() ) : 'Standard' );
// echo the result
echo $post_format_string;
?>

Codex ref: get_post_format(), get_post_format_string()