I've been messing with Silverlight for a few months now and I think it's the greatest thing since sliced bread! Expression Blend and Visual Studio development tools work in unison to make a great experience as well. You can use C# to code it, so you don't have to learn any funky new language like with Adobe products. Except for no built in mouse wheel support (really lame), there's nothing I dislike about it so far.
I've not used JavaFX at all.
Not to judge a book by its cover, but the examples of JavaFX on javafx.com look like garbage compared to the SL apps I've seen.
Has anyone on here gotten a chance to use both of the technologies? Anyone even using JavaFX can comment on their experience. Are there similiar tools as the ones Microsoft has for Silverlight (eg Blend, Visual Studio)? Does JavaFX require a plugin like Microsoft's SL does?