It will still be a thrill ride as the ride experience wont change, it will just be themed like a ride for children when it wont be a ride for children.
Why do you think that adding some angry bit signage to Dentonator is going to make it a children's ride? It's still a drop tower, just instead of vague pirate stuff and signs saying Detonator there will be bird bomb signs.
Also I am 32 and love the Angry Bird games, they are not something for Chrildren only really.
Did adding Sonic to Spinball at Alton towers make it a children's ride? No it was a spinning coaster and still is, just with a fibreglass Sonic outside!
Agreed, I'm not entirely sure what the fuss is about. Detonator will be the same ride (even retaining pretty much the same name), just with an Angry Bird feel, which as you say isn't a franchise aimed directly at children, in fact many older people enjoy it.
What confuses me is the area it will be in. The whole land is being fitted into a really small and quite bizarre area and will split the current amity (as I believe that's meant to stretch from Tidal Wave up to Stealth). I know Thorpe aren't big in theming, but this will seem a little disjointed I think...
However I do welcome the angry birds theme. Alienating families entirely was a terrible idea and it's nice to see Thorpe finally welcome them back (hopefully not too late) despite keeping the core focus of the park on big thrills. This years marketing, I think, looks really good compared to the past few years.