Can't wait for the WWDC announcements later today... I guess WO5 would be an obvious one. They've been developing it for probably 1-2 years by now, at least.
I'm pretty sure that Apple has made it clear that WO 4.5.1 will be the last native WebObjects that will support Obj-C. I think I heard it has tools to help developers move their projects to Java for WO5, but I haven't got WO so I can't really say.
WO5 will be completely Java, and therefore portable. This is a good thing for Apple - WO5 will run on just about any enterprise system under the sun (Solaris, Linux and *BSD would be the obvious new ones). I'm not sure if being written entirely in Java will affect the speed of WO, but I certainly hope it won't
