My wife complained of the same thing with our 03 today. I'm taking it in since I'm still under a 3 month warranty from the dealer. In reading about this on the web, seems it is going to probably be either the steering angle sensor or I've also heard the wheel speed sensor causing similar symptoms.
I'm also wondering if there was some actual loss of traction due to the inferior Goodyear Integrity tires on our MDX. Those things are garbage, so I'm just having to go from my wife's account of what happened. I drove it this morning with no further issues at all. :/
Hers: 2003 MDX (stock for now)
His: 2005 G35 w/mods