Google revealed its long-awaited wireless plans today — but they didn’t include the hotly-anticipated “Gphone.” Instead, the Internet search giant has formed an alliance with 33 manufacturers, carriers and other companies to make an open platform for mobile phones. Called Android, the initiative is an effort to make phones cheaper and spur faster innovation.

The announcement ends two years of speculation that Google was building an actual phone. But according to Google chief executive Eric Schmidt, there won’t be any one ‘Gphone’ — the company hopes there will be many, made by multiple manufacturers. “It is incredibly important to say that this is not an announcement of the Gphone,” said Schmidt during a conference call with Motorola’s Ed Zander, Deutsche Telekom’s Rene Obermann, Qualcomm’s (QCOM) Paul Jacobs and Peter Chou, the head of Taiwanese phone manufacturer HTC. ” “We hope there will be thousands of Gphones.”

But Google and its partners offered few clues today as to what any of these phones would actually do or how they would look and feel.

The first phone to run on Google’s Android platform will be one made by HTC, which the company says will be available mid-2008. HTC wouldn’t disclose details on what that gadget will look like or do. But Chou told Fortune it would be a global phone that would take advantage of the company’s capabilities, such as its touchscreen technology.

Chou said that he has been in talks with Andy Rubin, the Google executive who has spearheaded the Android platform, for over two years. Asked how he could keep Google’s mobile plans and collaboration with HTC secret for so long, Chou said he had to be “very disciplined.”

Google (GOOG) said its new Linux-based platform was born out of its frustration with how wireless carriers tightly control the software available for phones and which handsets consumers must use. The company says it will allow phonemakers to deploy its Android platform “under the most liberal open source license” and to make any mobile applications available on their phones. Among those that have joined forces with Google are Motorola (MOT), T-Mobile (DT), Sprint (S), HTC and Qualcomm.

“We want developers to start building applications to do the amazing things you do on the Internet on your mobile phone,” said Schmidt. “We’re saying to developers to build applications and please get ready for a device in 2008.”

Obermann, CEO of T-Mobile’s parent company, Deutsche Telekom, said Android will enable customers to “meaningfully enhance and personalize their mobile experience.” Details of how and when T-Mobile’s Android-powered phones will hit the market will be disclosed in the coming months, added Obermann.

Also part of Google’s new alliance is phonemaker Motorola, who already sells several devices running on an open-source Linux-based operating system. The new platform would be “complimentary to our open source strategy,” said Zander said during the conference call.

Notably missing from the alliance are major mobile phone players like Verizon Wireless (VZ) and AT&T (T), the two largest mobile operators in the United States. Apple (AAPL), on whose board Schmidt serves, was also missing in action. But Schmidt said the Android platform is open to anyone who wants to contribute, and that he hopes many additional companies will join the alliance.