Typically in Commander, Open the Vaults has been used to bring back artifacts more than Enchantments. Sydri, Galvanic Genius and Sharuum the Hegemon have made a place for Open the Vaults for quite some time. Hanna, Ship's Navigator has made the best use of Open the Vaults in the format, as she can bring back either an artifact or enchantment to your hand. Additionally, Kemba, Kha Regent likes the artifact reanimation, too, since Kemba revolves around Equipment, which happen to be artifacts. This puts them all into play, which for only 6 mana can be a devastating late-game play. .
To a lesser extent, Open the Vaults has seen play in some Aura-based decks for Commanders that need a way to get back their Enchantments quickly. Replenish from Urza's Destiny actually does that particular job better. Replenish only brings back Enchantment cards from your graveyard. But despite costing only 3W, it is a fairly rare card to get at this point and holds a high price tag.
Open the Vaults brings back more cards (albeit your opponents' as well) for 4WW, but it costs a fraction of the price. Commanders that don't mind having both this and Replenish in their decks include Uril the Miststalker, Bruna Light of Alabaster, and Zur the Enchanter. Other popular Commanders that use Open the Vaults include Breya, Etherium Shaper and Daxos the Returned.
While the Commander deck reprint depressed the price of the original Magic 2010 printing, the reprint did get copies of this very useful card into more hands. Also, Magic 2010 foils were unaffected by this printing. Interest in this card also increased, as is the case with many cards that are reprinted in a pre-constructed Commander deck. This is a great reprint and fits quite well into the deck which contains it.