http://graphicssoft.about.com/b/a/176541.htm
"Today Microsoft has released codename "Acrylic" as a time-limited, free trial beta version of a new illustration, painting and graphics tool based on the excellent Creature House Expression 3 software, which was acquired by Microsoft in 2003."
"Windows XP SP2 is required to run the software."
Huh, I run SP1 and it installed fine.
My quick review: an innovative toy but has still a long way before to be intuitive. For example, the control for the brush size maximum width is still located in the Preferences (!).
The control panels are un-docked but they should be re-dockable (or is that an SP2-only feature?) like in the original Expression3.
The "Export To Flash" is gone?! I get the feeling MS is dumbing down the program...
From the screenshots I saw, it looked horribly cluttered. Graphics programs are too eager to copy the millions-of-palettes design of Photoshop, which really is its weakest side, interface-wise.