With the explosive growth in spin-polarized electron transport studies for spin-tunneling, spin-transistor, and magnetoresistive device applications, the importance of layer switching, interfacial magnetic roughness, and magnetic domain correlation is becoming increasingly apparent. Since the spin conductance of a magnetic heterostructure is controlled by the relative orientation of the magnetic moment directions of the component layers on a local scale (within a few spin mean-free-paths), quantifying these mechanisms on this length scale would be very advantageous. Combining magnetic circular dichroism and resonant x-ray scattering, soft x-ray resonant magnetic scattering (XRMS) has a demonstrated capability to determine the order of layer switching, extract parameters which independently characterize the magnetic and chemical roughness of an interface, and statistically quantify magnetic domain correlations. Recent results for CoFe/Cu/SiN3/Si thin films grown with different Cu buffer layer thicknesses show conclusively from both the perpendicular roughness parameters and the in-plane correlation lengths that the interfacial magnetic roughness is much smoother than the interfacial chemical roughness. In Co/Cr/Co trilayer structures, angle and magnetic field dependent XRMS scans used in conjunction with MCD element-specific magnetic hysteresis loops are used to statistically determine that magnetic domains are vertically anti-correlated (preferrentially anti-aligned), indicating the presence of interlayer anti-ferromagnetic exchange coupling.