My daughter Rosalind (nearly 16) has taken to using the expression excited for rather than the more usual excited about: eg she might say “I’m excited for Latitude” (actually she said that today) rather than “I’m excited about Latitude”. All her friends say this too. And so does her brother, who’s 11 (although maybe he picked it up from her).
I wonder where it came from? I’m inclined to think that it is a direct translation of a structure from another language. No idea which one. Of course London is full of second-language speakers and school is an ideal environment for new idioms to spread. I can see why this one caught on: excited for sounds more engaged, more involved than the chilly excited about. But I don’t think I’ll start using it; it wouldn’t sound right from me.