Zone Telecom is offering a wholesale MVNO plan for service providers. So does Sprint (ping me for more details).
Many MVNO models have already failed and bailed. Cbeyond, Deltacom, Lightyear, and Touchtone are stilling giving it a try albeit with various models. Cbeyond and Deltacom sell mobile extenstions off a T1 service. Touchstone just sells mobile. Lightyear utilizes two channels: indirect agents and MLM.
"But new research from Strand Consult has warned those interested in becoming MVNOs that few can survive in what is already a highly competitive sector. [fiercewireless]
It gets even tougher as the smaller players like MetroPCS and Sprint go low, low price. Then you have retail giants like WalMart and Best Buy joining the fray. It's a flat market. The only reason to enter the fray is if you have some integration with the PBX. It's an attempt to get the majority share of the Total Telecom Spend.