Sounds like pure BS to me. I am pretty sure Lucas didn't really release false news either. Any news from official channels is typically taken very seriously. Had they really released a mock up teaser poster for Episode III featuring unrealistic amounts of Jar Jar, it is likely to have received a good deal of buzz, but yet it didn't get so much as a post here. Same thing for the 100% CG Anakin (which would have been good news for me, probably would have been an improvement). Also, had any of these things really happened, they would be documented somewhere. The Jar Jar poster would be easily found online, and some quote about the nonsensical choice to make Anakin 100% while all other actors remained live action would also surely be an easy find. People get good kicks out of well pulled off hoaxes and tend to remember them, if a hoax cost 8 people their lives, then you can bet the internet wouldn't soon forget about it.

The short of it, no none of these things ever happened.