A few more, in the news/magazine/talk genre:
One of NBC's '80s news magazine attempts, "Monitor", becoming "First Camera", and fading into oblivion.
Tom Snyder's "The Tomorrow Show" becoming "Tomorrow: Coast to Coast".
Local "A.M. Chicago" morphing into "The Oprah Winfrey Show"/"Oprah".
WABC-TV's local "The Morning Show" becoming "Live with Regis & Kathy Lee", and eventually becoming "Live with Regis & Kelly".
"Early Today" on NBC becoming "NBC News at Sunrise", then back to "Early Today" (as a CNBC production).
"A.M. America" becoming "Good Morning America" (though you could argue the latter was a flat-out replacement for the former).
and CBS's many variations of the 7am-9am period: "CBS Morning News", "The Morning Program", "CBS This Morning", "This Morning", and finally "The Early Show".