Microsoft Silverlight

Wow, it appears that "WPF/E" has a better RTM name than the other W*F parts.  That's right, "WPF/E" is now called Silverlight (via Soma's blog).  Also, don't let the name confuse you, if you have already the "WPF/E" Feb CTP, you already have Silverlight installed.  They've just renamed the install packages.