The Midrash describes the Divine consideration that went into endowing the city with its final name.
"If I call it Yireh like Avraham did, the righteous Malki-Tzedek will feel slighted, and if I call it Shalem like Malki-Tzedek did, the righteous Avraham will feel slighted. I will therefore call it Yireh Shalem Yerushalayim to satisfy both."
means peace and perfection while Yireh
means service of G-d. Only when man serves Hashem can he hope to achieve the peace and perfection symbolized by Yireh-shalem Yerushalayim. (http://ohr.edu/yhiy/article.php/1495/print