sources from Kaizoku Fansubs gave this french link. plus, it has also been listed on the One Piece Wiki page.
so i'm guessing more or less 100% confirmed.
now the only thing left is to find which of the online japanese stores are selling the DVD.
after reading through the article again with my less-than-desired japanese skills, i found (plus confirmation from ah gu) that the DVD that is going to be released is in fact NOT the Strong World movie, but instead Episode 0 + the TV specials that aired last November (Ep 426-429) about Little East Blue.
goes to show you can't really trust everything you read unless you've double or triple-checked your sources.
i'm depressed now.
confirmed + reliable sources says that the real movie DVD will be out in late August.
there is still hope yet!