I have been aware of the Cuckmere Have thing for sometime, but I thought they were only going to flood the west side to start with, before doing the whole thing.
As far as my opinion goes I think its great from a birdwatching point of view, and even better for birds, even if some of the locals are displeased.
As long as there are some pools/scrapes provided i cannot see any valuable habitat being lost (most of the area is just grass at the minute!) and it would provide great habitat for those all important breeding waders (Redshank, Lapwing et al.) as well as more passage and wintering coastal species.