At the same clock rates, the Northwood will outperform the Prescott, overall. The added benefit being the Northwood consumes much less power and generates far less heat as well.
Generally, the only thing the Northwood will not do better is overclock. The Prescott overclocks pretty well, but the heat will almost aways be a problem in an ATX case. It's not that the CPU cannot stand the heat, but the surrounding components are at risk.