Well, when I get out of the saddle to sprint, front suspension really soaks up my energy. Not good. But, if your suspension is not bobbing up and down, it isn't hurting anything.

Another option - most bikes have a 40/60 (F/R) weight distribution. That means you can usually run your front tire at its minimum inflation pressure and have the same rolling efficiency as your rear wheel. Detailed power measurements show this has no affect on rolling efficiency. Plus, your bike will have a lot more traction on rough roads or loose terrain. Just ask the mountain bikers or cyclocrossers.

Try putting 10-30% less air in your front tire than your rear. It will improve both the ride and the traction with no drawbacks.