TreoCentral forum member Malatesta has taken the task to gather details on upcoming Palm smartphones. He combined the info from FCC filings, rumors, speculations and so on. This info is based largely on small amount of official details, it shouldn’t be treated as an actual Palm roadmap:

• Codenamed Otto (possible product name Treo 500w) supposedly a Treo 500v quad band GSM version released from Vodafone in October for the Ammerican market.
• Gryphon or Gandalf (possible product name Palm Centro/Treo 690): a Sprint version of Palm Centro has been already released, the company might release a version for other CDMA-operators: Alltel, Telus and Verizon.
• Zeppelin (possible product name Treo 800w): rumors suggest this is the new flagship device. It is based on a 400 MHz processor and 256 MB RAM. This will be the first Palm smartphone supporting EVDO REV-A and Wi-Fi. It will be released on Verizon and Sprint in the US in 1Q 2008.