You have to realize that there is more to these ATC incident reports in the US than meets the eye...
Underlying the whole ATC delays/incursions stats are the fact that the controllers in the US are seriously pi$$ed-off right now at the FAA and the Gov. for imposing a 30% pay cut on them. The Dems realize this and are trying to pass legislation to force a re-opening of the contract, something which Bush has said he will veto (his administration is on a massive anti-employee purge in the aviation sector - a long-standing grudge between the GOP and aviation workers, and unionism in particular).
The FAA is trying to gloss over the whole thing with its stats...the reality is the controllers will simply step up action, such as enforcing mandatory in-trail approach separation on vmc days, as long as this contract festers with them. Nearly 1000 experienced controllers have resigned since the imposition of the cuts, and this is negatively affecting staffing at all levels - possibly contributing to incursions. The reporters here are starting to pick up on this, and the FAA is starting to appear more and more embattled.