The new windows pro pads with full fledged windows 8 pro, will give the ipads a run for their money as all the windows pro apps will run on an Intel i5 or even i7 pad with windows 8.
Dont get a windows RT pad tough, as those are ARM based and dont run the professional windows music programs and VSTīs.
I think these new windows pads have much more to offer to a musician then an Ipad, because they have 0 times the processing power of an Ipad, espescially those that use full fledged Intel processors and not Attoms.