yes, good for macro, but key uses are correction of perspective in shooting up or down at big things like buildings, and best of all for infinite depth of field at near wide open apertures for landscapes where you can't afford long shutter speeds (e.g. where you don't want movement blur)
I got the 24 for perspective (but it does well at semi-macro with tilt) and the 90m for macro with tilt not shift.
Read about these and rent so you can try. I'd only do it with a body that has live view.