Recently, the car has been making a continuous thumping sound from somewhere in the front of the car. At first, I thought it was the tires because it gets louder and faster as I go faster... and is very noticeable above 45mph.
I hope its not a bearing - sounds like it, though. But... there's usually no excessive vibration from the steering wheel.
I think... to describe the sound itself... It sounds more like a wobble at low speeds and goes on to be somewhat of a helicopter wooomph at higher speeds.

It's an 05 GT with just over 70,000 miles and I've meticulously kept up with all the recommended maintenance.

Any ideas? I just wanted to post on here before I take it to the shop to see if anyone can point me in the right direction regarding what this might be.

 

Inspect it. Jack up the front end and turn the wheels, if it's a bearing you should be able to hear/feel it. See if anything is loose. Did you lock up the brakes recently? That can flat spot the tires. Check all the suspension and steering linkage, and the brake hardware.