(1) Exciting an intense but usually brief interest or emotional reaction. (2) Extremely or unexpectedly excellent.
Example:
The sensational newspaper accounts of the marital problems of the royal couple fascinated many readers but made others a little uncomfortable.
The photos sent back from Jupiter by the Voyager satellite were sensational -- both excellent and exciting. The murder of a pregnant woman by her husband was sensational also, although in a very different sense, since it was picked up by the tabloid press and sensationalist TV journalists, who thrive on such sordid tales and sensationalize every detail. Both stories, however, can be said to have created a sensation.