An article that appeared on Apple's support site Tuesday doesn't appear to be directed at any other company in particular--unless you read between the lines.
Titled "iTunes: About unsupported third-party digital media players," the article addresses the claims of "some third parties" that their digital media players are able to sync with iTunes. By "some third parties" they clearly mean "Palm," which has manipulated the new Pre smartphone to sync with Apple's music software. Palm execs showed off the iTunes sync feature at last month's D: All Things Digital conference.
The article reads: "Apple is aware that some third parties claim that their digital media players are able to sync with Apple software. However, Apple does not provide support for, or test for compatibility with, non-Apple digital media players and, because software changes over time, newer versions of Apple's iTunes software may no longer provide syncing functionality with non-Apple digital media players."
That can be taken as a none-too-subtle threat that Apple can break the Pre's iTunes sync capability with a simple iTunes software update any time it wants to.
Apparently Palm's chief investor Roger McNamee didn't see this coming. When he and Palm CEO Jon Rubinstein introduced the feature, he acknowledged that Apple could take legal or technical steps to block the feature, but said, "I find it hard to believe they are going to get bent out of shape."