Re: My conspiracy theory tells me that IDF is really the place for Intel to show the best they've got.
The environment has also changed. People obviously won't be impressed with the latest overclocked Prescott demo to 5.0GHz on LN2 cooling. These were the dog and pony exhibits of the prior IDF's. I think it's more impressive now to show 4-way Montecito demos that appear as 16 threads under Windows. That says a lot about the early health of Montecito and offers a higher confidence that it will appear in the second half of 2005.
The also demoed Sonoma, next year's mobile platform, and announced early details on Napa, the dual core mobile platform of 2006. It seems to me that Intel has a very clear direction in terms of their mobile and IPF parts. As you said, IDF is a technology showcase locale, and it seems that Intel has indeed taken advantage of that.
On the other hand, their mainstream plans have been left as a mystery. It's no wonder that it gives you the impression of a directionless Intel when they fail to outline the roadmaps for the desktop and mainstream server markets. Other than announcing that dual core will be an inflection point in the market, they were pretty vague. Perhaps it makes sense not to expose their plans this early, or perhaps they are still awaiting functional silicon. It's not clear, however, that the absence of details is a reflection of no future plans. I think Intel is simply keeping the details secret to their NDA partners.