The only Diablo-related project Blizzard is working on is patch 1.10, which is large enough a patch that they need to devote all their time to it. I also doubt that Diablo III was supposed to come out in 2001. Diablo II came out in what, 2000? A single year is not enough time for Blizzard to make a full game. Hell, it takes them nine months to come up with a good expansion for a game. It just can't happen.
They don't make sections for games they have yet to announce. Why? It's illogical. When they announce StarCraft II, a section will be opened and totally devoted to StarCraft II. No announcement, no section.
What are your sources for this so-called information?