Ilusionado comes from the noun ilusión and shares its positive meanings of hope and excitement.
Spanish: un grupo de jóvenes demócratas ilusionados English: a group of young democratic hopefuls
Spanish: Está ahora muy ilusionado con su nuevo proyecto. English: He's very excited about his new project.
In the structure estar ilusionado con algo referring to a future event, it often means to look forward to something:
Spanish: El equipo está muy ilusionado con la apertura del nuevo restaurante. English: The team is really looking forward to the opening of the new restaurant.