This sounds like a good commercial move. As noted by theenglish
magic and monster films have had recent success. WB look no farther than Harry Potter but Percy Jackson is also filming it's second movie and Hobbit back in the mix for monsters on film.
A JLD film using the right mix, on paper, sounds like a possible winner. The only character that sounds a bit forced for the group Del Toro mentioned is Swamp Thing. It may be that including him is a set-up for a spin off though!!
Another thing it does is avoid being seen as blatantly trying to ride the coat tails of Avengers, like JLA appears(can't blame them though). It also doesn't mirror X-Men. It's a team of magicians and other supernatural types with other angles to explore.
Don't know how "hot" the current JLD comic sells but I've enjoyed it and Constantine is the core of that title and now he's spinning out into his own title this Spring.