Verizon officials did not respond to a request to confirm the March 17 sales date, which has been the rumored launch date since last week.

Wirefly is lending weight to the Thursday launch date, saying it will begin to take online pre-orders for the device at 3 a.m. ET tomorrow. Shipments of the device are set to begin on Thursday, Wirefly says.

Wirefly's special price, still unannounced, will be available when sales begin, a Wirefly spokesman said. The retailer has on its site.

The spokesman said he had received a document from Verizon sent Monday that said, "The wireless devices group introduces the HTC ThunderBolt to the product line-up! The HTC ThunderBolt will launch on March 17, 2011!" The spokesman would not share a copy of the document, however.

The Thunderbolt has been teased in repeated national TV commercials for several weeks, almost back to the in early January, when Verizon , including three other , that it will introduce by the middle of 2011.