Suzanne,
You're right--MathType Lite a.k.a. the MS Equation Editor is still in Word
2007 (at least the compatibility is there, if not the old UI).
I'm wondering, though, about the regular version of MathType. As of Beta 2
TR of Word 2007, MathType's special Word add-ins don't work (the MathType
menu and toolbar).
It's not surprising, since Word 2007 doesn't have toolbars or menus.
But
I'd love to see Design Science come up with a Ribbon-based add-in for Word
2007.
I should mention that you CAN use MathType with Word 2007 just as you would
in any application that supports embedding objects. What's missing are
commands like "Format Equations" and the like.