Ringback tones are hot. Virgin Mobile USA and partner LiveWire Mobile say more than 5 million Virgin Mobile customers currently have access to more than 10,000 songs within LiveWire Mobile’s Ringback Service.

Virgin Mobile customers average two ringbacks per customer. The most popular tones are in the hip-hop and R&B categories. Some of the top tone titles are: “Shawty Is A 10” (The Dream); “Bed” (J. Holiday); “Heaven Sent” (Keyshia Cole); “Crank That – Tell ‘Em/Ne-Yo Chorus (Soulja Boy); and “Apologize,” (by OneRepublic featuring Timbaland).

NMS Communications announced LiveWire Mobile in December. It’s a division of NMS committed to delivering mobile personalization services to operators. LiveWire’s ringback service is deployed with more than 30 operators worldwide.

Other carriers working with LiveWire include Cricket, Rogers, 3 and Vodafone.