Where it is!

Is it grammatically correct to end a sentence with a preposition?  My pet peeve is people who end a sentence with the preposition at!  Now even college professors speak this way. 

In 1961 Chris Kenner wrote a song called, “I like it like that.”  Apparently he needed a word to rhyme with that.  He took poetic license to end a sentence with at, which is acceptable in a song, but not in speech.  Since then ending a sentence with at has been accepted more and more. 

Will we ever recover?

Come on (Come on, let me show you where it's at)

Come on (Come on, let me show you where it's at)

Come on (Come on, let me show you where it's at)

The name of the place is (I like it like that).

What the song says is let me show you where it is.  The word at is not necessary.  Therefore it is not needed at the end of the sentence. 

I am not bothered by a split infinitive however.  “Boldly going where no man has gone before” is fine with me!