Seepweed?

Yesterday I ran into a product at the local Mexican supermercado that I've never seen. It's labeled seepweed and sold frozen in a 2 lb. package. I almost bought it on a whim (it had a recipe on the back with shrimp and looked like a mix between seaweed and a pine shrub), but then realized it was $18! Wanted to get a little more info before the purchase.

Anyone ever heard of it? Or, better yet, eaten it? I found this on Wikipedia, which doesn't help a whole lot.

http://en.wikipedia.org/wiki/Suaeda