Sort of. The shadow realm is like the ghost zone, except its where shadow monsters live. If I choose to let them live. My shadow creatures are created by me and I can either destroy them or let them live there. If I really wanted to I could learn to summon the really powerful shadow creatures that were born there, but I'm probably not strong enough to control them...
Its also is where forgotten knowledge goes...the challenge is finding it in the vast library of books...well...scrolls...
Its kind of like an inbetween world between our world and the realm of darkness...