The California Supreme Court ruled today on Prop. 64, as most of you are likely aware. The rulings are Solomonic: yes, Prop. 64 applied to pending cases, but, yes, you can amend to add people who were affected.
The Supreme Court did not address to too-clever-by-half "statutory repeal" rule that many of the lower court rulings had depended on. The Court instead relied on the substance/procedure distinction.
Of course, this is all well and good, nearly two years beyond the election that put this law into place.
My analysis is that the Supreme Court is in the process of walking back some of its strong anti-retroactivity opinions of the early part of this decade and the late 1990s.