You'd think network execs would know this stuff....

Studio 60
A group of network honchos are discussing a possible new "reality" show with a romance theme, which they have titled "All You Need is Love". The following dialogue follows:

Hallie: We can't get the rights to the title "All You Need is Love"...

Jordan: The Beatles said no?

Hallie: There was already a show that used it.

Jordan: Damn it to hell!

Anyone with even the slightest knowledge of intellectual property law (even a layman like myself) would have known that there were no "rights" to get. Copyright law does not protect titles, short phrases, or words, and unless the Beatles or the producers of the prior show had filed for trademark protection and still have an active interest in the name, the name is freely available. The case can also be made that "all you need is love" is a common phrase known to be in use long before either the song or the show in question.

There have been many shows, plays, books, movies and songs that use the same title, and it is perfectly legal and proper to do so. A search of the IMDB will turn up many such examples...

Saving Grace (movies in 1985, 1998, 2000, and a 2006 song by Tom Petty)
Crash (films in 1922, 1977, 1987, 1996, 2004, and several TV shows)
Bombshell (1933, 1935, 1996, 2006)
... and so on.

In addition, there are a lot of films with titles based on songs, including:

Blue Velvet
And the Band Played on
Boogie nights
Man on the Moon
Can't Buy Me Love
Sixteen Candles
Uptown Girls
My Own Private Idaho
American Pie
Happy Feet
Pretty Woman
Some Kind of Wonderful
Beyond the Sea
Down with Love
When a Man Loves a Woman
My Blue Heaven
Sweet Home Alabama

...and so on.

There is absolutely nothing to prevent Hallie's show from going forward, except maybe the boundaries of good taste.