The new guidelines make a lot of sense. With age, arteries get stiffer and less elastic. Systolic pressure (the peak pressure in the arteries as a result of the ejection of blood from the heart after a heartbeat) would be expected to be higher in stiff arteries than it would be in more elastic arteries. So a slight increase in systolic pressure is just a normal consequence of the aging process.
The new guidelines are just that; guidelines, based on the best available evidence. The panel fully expects that the recommendations will be discussed and debated by physicians. It will be interesting to see whether the American Heart Association eventually adopts the new guidelines; currently it still recommends that blood pressures be lowered to 140/90 in all hypertensive patients.