The success will depend a lot on the chipset. If you are staying with the same chipset manufacturer (ie: VIA to VIA or nVidia to nVidia) the chances are much higher... Crossing from one chipset to another may cause some grief however...

I guess the best way to know for sure is to give it a shot. Either way, I'd still backup your important files first before swapping boards and booting/reinstalling the OS...