Virgin Mobile USA -- the no-contract wireless service that introduced its “Higher Calling” promise to customers earlier this year and which recently launched the iPhone with unlimited data and messaging plans starting at $30 per month -- has once again received the highest ranking in the J.D. Power and Associates 2012 Wireless Customer Care Non-Contract Study, this time for Volume 2, released Thursday. According to J.D. Power and Associates, Virgin Mobile USA’s overall index score was significantly higher than the industry average, 750 vs. 701, and higher as well than its score of 735 from February’s Volume 1 study, in which Virgin Mobile also ranked highest among non-contract carriers. Virgin Mobile respondents included Beyond Talk, payLo by Virgin Mobile and Broadband2Go customers. A link to more information about the J.D. Power and Associates award and Virgin Mobile USA’s performance can be found here.