2011-03-21 simon.fraser@apple.com
 - Removed "Module Level 3" from the title.

2010-12-14  simon.fraser@apple.com
- Clarify that a percentage z-value for transform-origin, and for translate3d() and translateZ()
cause the property to be invalid.
- Fix wording of of "Percentages: refer to..." for transform-origin.

2010-09-07  dino@apple.com

- Mark CSSMatrix as [Supplemental]
- mark some arguments as optional in the CSSMatrix IDL

2009-10-30  dino@apple.com

- perspective now takes a Length value
- described what the reverse face of a transformed element should look like