'Pulsating' noise between 50-60mph

At highway speeds (50-60mph on freshly paved roads) I hear what can best be described as a pulsating noise coming from my front end. When I brake the noise becomes more pronounced and if I brake hard enough, I can feel it in the steering wheel. Otherwise, I do not feel the noise when it can be heard.

My initial thoughts were a bad alignment/out of balance wheels since I've had to have all four wheels aligned twice in the last yea, perhaps the tires have uneven wear as a result of being out of alignment? After the most recent alignment and balance (early August 2012) the noise wasn't as pronounced unless on a freshly paved road or under hard braking.

All repair work/oil changes have been performed at the Honda dealership it was bought from since new. I was told the bearings are OK. The front brakes were last replaced about 25k ago by Honda. Maybe the front brakes are on their way out or the rotors need to be turned? I do a lot of mountain highway driving. I also experience a lot of stop-and-go traffic on the way to work, so there is heavy brake usage. I don't hear the typical 'squeal' that usually happens when pads are about to go out.

The question is: Should I take the vehicle to a different Honda dealer to check for bearings, have the rotors turned, or look at something else?

The last major service was when the short-block was replaced due to cracking (thank god for service bulletins about this) at the beginning of August 2012 when the alignment and wheel balancing was performed.

Thanks for any help!