Verizon Wireless is the newest member of the LiMo Foundation, which exists to push the Linux open source operating system onto mobile phones.

Verizon joined at the Core level, which is the LiMo Foundation’s second tier. The carrier will have a seat at the board of directors and is the organization’s 40th member overall.

“Verizon Wireless is committed and invested in encouraging innovation, providing developers the opportunity to deliver new wireless choices and expanding the mobile market. We expect our involvement with LiMo to advance these principles,” said Verizon’s Kyle Malady, vice president of network technology development, in a statement this morning.

Malady said Linux will first be seen in feature phones, most likely in 2009, later moving up to smartphones.

Currently the foundation reaches 500 million subscribers worldwide through carriers in Europe and Asia, said Andrew Shikiar, LiMo director of global marketing. But other major U.S. carriers such as AT&T and Sprint are not yet members.

“I think that they’re all on their own timeframe… It’s a pretty profound decision to decide to join,” Shikiar said. However, “We’re in early conversations. Generally speaking, it hasn’t been a fear thing, it’s been more of an investment priority for these companies. I anticipate this being a ‘when’ question,” he added.

Also notably absent is Google, with its Android operating system based on Linux.  “Google is certainly welcome to join the LiMo Foundation as well. We see [Android] as somewhat of a redundant development effort,” Shikiar said.

The LiMo platform, announced last month, is currently in its R-1 status and already ships in some phones. Most of its code is from Motorola, NEC, Panasonic and Samsung. R-2 is due later this year or early next year and will include contributions from dozens of companies, Shikiar said. R-1 focused on baseline telephony functions and R-2 will include more advanced features such as Internet access, SMS, video, device management, Java and security.

Also, “What you’ll see from us later this year is a more formal way of engaging with the wireless developers,” Shikiar said. That will include a Website expansion with a developer focus and a software development kit, he said.

Other new members of the LiMo Foundation announced today include Infineon Technologies, Mozilla Corporation, Red Bend Software and SK Telecom.