I have both a hybrid and road bike. I purchase the hybrid first and use it for commuting. I purchased a road bike later because I needed to be more comfortable for long distances.

I find the road bike is more efficient and comfortable. Road bikes have a variety of hand positions and can change them regularly so my hands dont get numb, etc...

If you are spending some time off pavement I would agree with the cyclocross suggestion. It's very easy to swap the tires for some thinner road tires and voila - you have a pretty capable road bike.

If your not going off road at all - my suggestion would be to try a touring road bike.

I hope that helps.

-R