Now this is interesting.  Reported here, that Poynter studied people using eye tracking technology to establish how people read things. 

The reading-deep phenomenon is even stronger online than in print.

Source: Poynter Online – EyeTrack07: The Myth of Short Attention Spans

There are a million ways to discredit this kind of research, but on the positive side, I like the idea that people select what they want to read, one page at a time, and read it.  Online, and particularly when supplemented with RSS provides the capability to bring the news/ information that you want, to you.