Ahh, Lin... didja ever think it might be related to being in FL?
More seriously -- I used this trick when creating a mailbox bed and a larger bed beside my driveway back in summer 2008. The only weeds I really get in the larger bed are pine or sweetgum seedlings, and a little bit of grassy stuff creeping in from the sides. The mailbox bed gets more crabgrass, but still manageable.
Other areas I've tried it haven't been nearly as successful,but still better than weed fabric.
