Odd vibration at speed... any ideas what it could be?

Thanks for the reply. I'm not 110% positive it's coming from the front, but I definitely don't feel any vibration from behind or below like I've experienced with u-joints in the past with other vehicles.
The wheel bearing crossed my mind, but I guess I assumed that it would be something constant, not on and off like that.
I will check that out - thanks again for the reply! :-)