As of 8:10 PM EST Thursday night, Verizon customers were no longer able to preorder the iPhone 4 as the telecom giant shut down preorders after the most successful first-day sales in the company’s history.  The number of units ordered was not disclosed (at the unveiling event in January, Verizon wouldn’t comment on sales expectations then, either).

“This was an exciting day.  In just our first two hours, we had already sold more phones than any first day launch in our history,” said Verizon CEO and President Dan Mead.  “And, when you consider these initial orders were placed between the hours of 3 a.m. and 5 a.m., it is an incredible success story. It is gratifying to know that our customers responded so enthusiastically to this exclusive offer – designed to reward them for their loyalty.”

Until now, preorders for Verizon’s iPhone 4 have only been available for existing Verizon customers, but as of February 10, the Verizon iPhone will be available to the general public at all of the company’s 2,000 stores, plus Apple stores, Best Buy, Wal-Mart, and online.  Verizon currently serves 94 million customers.

Last month, the company revealed the CDMA-compatible Verizon iPhone and the future looks promising.  The Verizon iPhone will be able to provide hotspots for up to five computers, while AT&T currently only provides tethering for one.

Con: Verizon customers will not be able to use data and voice simultaneously.  Calls will always override data, which AT&T is capitalizing on in its latest ad (see below) reminding iPhone users that only AT&T allows customers to talk and surf at the same time.

Verizon and Apple have been in talks since 2008 and spent a year testing the phone to be sure to avoid the problems that AT&T encountered when too many users overloaded the network.

At the Verizon unveiling, Apple COO Tim Cook stated that Apple has entered into a multi-year, non-exclusive contract with Verizon, which suggests that other CDMA networks like Sprint could also be getting the iPhone.