It seems to me that Twitter, Google, and Wolfram|Alpha, are really not competing at all, but are instead providing complementary services. I would go farther by adding wikipedia (and blogs?), and suggest that the 4 services really represent the digestive process of our information society. From the first Churning to the Backbone
Wolfram|Alpha represents the deeper part. It includes only what is really known inside out from our society. What has been fully digested. FOr something to be in W|A it needs to be known, semantically known, beyond doubt. And notice that I am here speaking about a deeper Wolfram|Alpha than what you have seen here. The Wolfram|Alpha as it should be, once we learned hot to interrogate it proprtly, and once it has epanded with the rest of the knowledge we have.
At a higher level we have wikipedia. Wikipedia permits much more stuff to be present. You have actors, and theories, and stories, and a lot of other stuff. You also have discussions and point of views. In short you have a lot of stuff that is not being digested anymore, but is also not the bones of our society. It is more like the muscles. The limit of Wikipedia is that since it does not allow for new research, by definition it is limited to what has already been discovered. Although not in a definite way as in Wolfram|Alpha.
And then we have Google. Google is really part of the digestive process. It has new stuff coming in every few days. But is is also less clear. You need to work to get to the results using google. But you can also find new threads. Things that are still not known. There is real food here, waiting to be digested.
And Twitter is the more superficial tool. Twitter has second to second update. It has multiple links in different forms that point to the same resource. Information is not organised in any way, shape or form. But it is information nevertheless. It represents the edge of the knowledge wave of our civilization. It is deeply alive, unpredictable, full of possibilities. You never know how it will react. It is the most alive part of the constant discussion that is going on in our civilisation. It is the civilisation equivalent to the constant chit chat that is going on in our head. Although it has memory, it is not really good with it. Anything that is in Twitter can be true, can be false, can be anything in the middle, neither or both at the same time.
If you are an alive and creative mind that wants to participate in the constant flow of creation of this society you will probably end up interacting in twitter in some ways. But if you want your creation to be grounded in reality you need to use the other levels as well. They are really not competing.
And Blogs? Blogs are ways with which we store personal longer stories. The untwittable (as Chris Anderson from TED called his). They work between the google level and the Twitter level. Letting information move between those levels, and letting complex information be churned before is ready to go deeper. Similarly you have journal articles (and books) working to bring the information to the wikipedia level.
