I live pretty near to Six Flags Holland too, about a 45 minute drive, so I have been reading about all this. So here is the story behind it.
A british investment company called Palamon bought the entire Six Flags European Division, however I am not sure if Warner brother movie world Madrid was included. These parks were sold last year and next year the parks will be renamed, the company name will be StarParks and SFH is going to be renamed to Walibi World, because Walibi was sort of the root company which turned this place into an amusement park in the first place. Because the DC comics stuff can't be used anymore a few rides would have to be renamed and re-themed so that is promosing. There are also a lot of rumours about a new family ride for the next season, however, just rumours so far.
That's about it, from what I have heard so far it seems that Star Parks is not willing to invest in the parks a lot, and they want to attract more families, so we'll see how that turns out. I believe Palamon is planning to make the parks "healthy" again and then sell them in 5 years to someone else. They did get a guy from the Tussauds group in the staff for theming, so I hope he does some good things for the park, because theming and indoor rides is what SFH lacks.
Anyway, let's hope the SFED has a bright future ahead of it.
Never heard of Star Parks? Look here:
http://www.starparks.com/