I just received an email from "Chime", the developer of the WonderSilk application for the Sony Clie NX series PDA's, and he said that he has no development plans for Sony's new Clei UX series PDA's. He says this is because the UX does not support Silk Plug-ins like the NX series did.
I had some high hopes of converting many of my current WonderSilk Skin designs to the UX's vertical format. I also had some ideas for some new skins, but it looks like it won't happen. Major bummer!