Maybe people forgot about it because nothing came of what they promised.
Same goes for J.E Sawyer's Black Hound project - which was originally going to be BG3 (despite not continuing the storyline in any way) but got cancelled. Years later, Josh altered some of the content from the Black Hound proect into a still unfinished module for NWN2. Kind of understandable though given Sawyer's other big projects at Obsidian.
Here's some concept art for the original BG3 (Or Project Jefferson) that was abandoned.
https://plus.google.com/photos/11507...785?banner=pwa