Originally Posted by leobg
There is no requirement or restriction on this....
Leo are you certain it will take ClassIII memory? It makes sense just not sure the hardware did that.
to the OQ - If they come out with a newer class there might be a compatibility issue with the phone but XDA folks usually finds away to support them soon after via a patch.
Stay away from old legacy (Not Classed) SD cards. Go for the fastest and largest you can afford.
Android rely's much more on the SDcard than WM ever did.