It's REALLY difficult to have any one institution, one group of workers, divide their focus between two radically different models and succeed at both. Specifically, it's really difficult to produce a great newspaper and a great community web site at the same time. They demand fundamentally different things and force choices that slight one medium or the other.
In short, newspapers are doing the splits as they try to keep one foot in each of two diverging worlds.
His piece does a nice job of laying out, in concrete terms, how "the splits" divide a paper's resources and weaken its efforts.