I've been playing around with the idea of getting a new casual watch for when I'm outdoors and am wondering if there are certain considerations I should be taking into account if I expect to be wearing it while trying to navigate with a compass.

To what degree (if any) will a wrist watch interfere with a compass? Are some watches better than others with regards to playing nice with a compass (materials, movement, etc.)?

I'm not really experienced with navigating with a map & compass yet, but I got a new compass (Suunto MC-2DL) and a book (Wilderness Navigation) for Christmas and plan on taking some courses a bit later this year.