What is not part of the Marvel Cinematic Universe;

X-Men, Wolverine, and apparently the word 'Mutants'. However, they're now limited to the characters that have appeared so far. So, don't expect anyone to die anytime soon because Fox doesn't have the rights to any more X-Men - supposedly.

Blade
Spider-Man
Daredevil/Elektra (although that licence expires soon)
Punisher
Ghost Rider
Fantastic Four