Lycamobile have launched their US service...
Lycamobile | Low Cost international calls | Best international SIM card | Free SIMs
Preliminary data point to Lyca being a T-Mobile MVNO.
Pay per minute @ $0.04/minute for domestic calls.
$39/month for unlimited domestic calls, 100MB data and $10 international calling credit.
$49/month for unlimited domestic calls, 250MB data and $20 international calling credit.
VladS
Mobile phones: iPhone 5, Blackberry 9900, Nexus S, Samsung S3322 duos
Mobile data cards: Huawei E587u-5, Huawei E583c, Huawei E160
Postpaid SIMs: CA: Fido, Wind; INTL: Telna
Prepaid SIMs: DE: Fonic, Lidl; AT: yesss!, bob; UK: O2; US: AT&T; RO: Orange, Vodafone; FR: b&you, Lycamobile; NL: Lycamobile; BE: Lycamobile, Jim Mobile; CL: Entel; MX: Telcel; INTL: eKit Blue, eKit Yellow
Dead SIMs: too many to list