Why did Overture buy Altavista and FAST

I've kind-of ignored this recent action by Overture because I didn't really have an feeling for the benefit of the action (unlike Google's buy of Blogger, which makes a lot of sense).

This article (Thanks Brian) makes some hay out of it, as it affects "database publishers" (those that publish industry directories etc.). They see Overture making a big risk without a clear strategy that will disrupt the PPC marketplace. As a client of directories and Overture, their summary point is well taken:

Overture was rapidly becoming the obvious and easy answer for a lot of directory advertisers--usually to the detriment of directories...As long as paid search stays fragmented, confusing and expensive, database publishers have a window to establish viable vertical portals that provide a targeted and cost-effective alternative to most advertisers.

The future of Overture?