Diane Sawyer wraps her 'World News' run Wednesday

After a five-year run as anchor of ABC's "World News" - not to mention a career spent in preparation for that role - Diane Sawyer signed off Wednesday night for the last time. She will remain at ABC News, but her nightly chores are done.

Yes, the exit was of the stealth variety, and yes, there was a tweet, earlier in the day when Sawyer, 68, told followers that she was moving up her departure, from Friday of this week to Wednesday. "Great adventures ahead," she noted cryptically -- although Sawyer is expected to fill the role that Barbara Walters recently did, as the network's lead interviewer. She will be replaced by David Muir, weekend anchor of "World News" on Tuesday.

Last night's edition lead with a report about the release of journalist Peter Theo Curtis after being held two years in captivity by an al Qaeda wing in Syria. But it quickly segued to what Sawyer called a personal note: "Thank you to all of you as I leave the anchor desk."

Later in the broadcast, Sawyer narrated (and of course starred in) a congenial -- and generous -- salute to her staff and colleagues at "World News," then later concluded with a little bit more generosity: "What a deep privilege it has been to serve a broadcast where Peter Jennings created the signature of such curiosity and courage." Jennings, who led "World News Tonight" (as it was then called) to the ranks of TV's most influential news broadcasts, died in 2005 at age 67.

Sawyer's final salute: "With gratitude for these years, I thank you."