The link is to a short article in The Register in which desktop search functionality is described both as an opportunity for malware authors to ply their trade and as a possible adjunct, or even a core function, to security services. After all; your anti-virus and the search utility are both scanning the same files, at least in the main. Some research is being performed on uniting the two scanning functions.
The article makes clear that right now, conventional anti-viral scanning applications are faster and more thorough, in part because search functions do not have access to kernel-level functions and processes. However; as search is more tightly integrated into operating systems, this can be designed in and it might make a whole lot of sense, both in terms of resource conservation (and related efficiencie) and real-time protection.
Food for thought