Hidden Heart Risks for Marathoners?

FOA Ryan passes along a link to a Bloomberg story on research indicating that marathon running may pose a heart risk for men age 50 or over. Running 26.2 miles never feels healthy and I don't recommend it to people who ask. But the lifestyle and discipline marathon running demands of participants who stay with it over time would seem to provide plenty of health benefits that outweigh the risk of heart troubles during a single race. So do all the training but don't race the full distance? Based on how 2006 has gone, I'm on my way.