To ask whether or not Google should be worried about Wolfram|Alpha might seem a bit premature. But one thing is quite clear whether Google realizes it or not. Wolfram|Alpha and technology like it could one day be a real threat to Google’s supremacy.
Despite this possible threat, one thing that cannot be overlooked is Google is very good at branding. And to be honest, I think that they had an above fair push from the now defunct TechTV. Let me explain. Back when the network was still intact, nearly every show on the network was making references to this up and coming wonder. And it became more popular, the network’s usage on air became ever-frequent.
Now considering that at the time, there is no way that word of mouth alone helped Google spread as fast as it did, I would say that Google has plenty of time to “catch up” as needed considering there is no longer a TechTV network reaching the same audience and explicitly speaking about this new Wolfram|Alpha search engine prototype. Will Google one day be taken to task? I find it highly unlikely based on perception and branding alone. I just do not see it.