Whats your mileage, and has it been regularly maintained?
wheel bearing is a good bet. I had to replace both of my fronts at 150k along with both of my CV Joins, and then had to do it all over again because a faulty reman CV joint destroyed the brand new passenger wheel bearing. They can fail at pretty much any time, but its a wear item.
Do the shake test on the wheels (check for play), or determine if it is a bearing by turning right/left and noticing when the noise lessens or stops. If turning left, its the passenger side bearing, etc.
On a side note, make sure all of your window seals are good and the windows not just partially lowered. I almost pulled my hair out earlier today because my window seal is failing and I had a constant wind whine
