Sure, they use it generate interest. I certainly hope they do. But what if they did something else instead?
What if the rumor-mongered to generate ideas?
Apple seems to do it all the time now too. Maybe it's just looking for a conspiracy when there isn't one, but think about it. What a great business model:
1. Think about something that people are dissatisfied with and is lagging technologically.
2. Use your reputation and clout to monger a rumor about an "upcoming" product.
3. Cherry pick ideas generating by hundreds of people.
4. Develop and polish product.
Seems pretty simple to me. You off-load all of your speculative R&D efforts onto the public. That is probably the most cost-intensive portion of any company that relies on innovation. Brilliant!