Over at The Register I wrote about my recent experiences playing with (whoops, evaluating) JavaFX. (Note this is part 1 of 2 articles). Judging by the comments, and also comments from the folks in the JavaLobby community, the article's being read as "This guy's saying that JavaFX is doomed already."
Yes in a sense, if the project remains on its current course. A pretty major problem is that Flex, already at version 3, is leaps and bounds ahead. But Flex also happens to be more well thought out.
One example that I don't mention in the article is with stylesheets. Whilst trying out JavaFX, I found myself thinking: "It would make so much more sense if these components could be styled using a separate CSS file."