Check the phase - out of phase speakers have sound coming out of nowhere. Put on a cd with a well-centered vocal like Nora Jones and make sure she's coming from dead center. If not, your speakers are out of phase or you moved them to such a wacky position that there's no imaging. Soundstage denotes the illusion of the musicians spread between, behind and in front of the speakers, but everything should be identifiable in terms of location, IMO. If you can't tell where the performers are, something is probably screwed up.
Not seeing the sound
The other day, I was playing around with speaker positioning, and hit upon a spot where I could no longer "see" the sound coming out of the speakers directly. Now, the sound seems to be in different places relative to where the speakers stand, sort of in an etherial way. I like it. This may be a dumb question, but does this mean I've finally gotten a "soundstage?"