As to the question what children are poking fun at now, one answer is the big purple dinasaur, Barnie.

See: http://en.wikipedia.org/wiki/Anti-Barney_Humor

Here's an excerpt from that Wikipedia article:

I Hate You" is the best known of the written anti-Barney songs, commonly sung by children in elementary school who have recently grown out of the show[5]. It is a parody of the show's closing song "I Love You", which is itself played to the tune of "This Old Man". There are numerous variations, many of which start with the lyrics "I hate you, you hate me, let's get together and kill Barney" and then change into something different.

Examples:

I hate you, you hate me,
Let's get together and kill Barney.
With a one punch, two punch, three punch, four
No more purple dinosaur!

I hate you, you hate me
Let's get together and kill Barney.
With a piece of glass and shove it up his ass
I've never seen a dinosaur run so fast


I hate you, you hate me
Let's go out and kill Barney
With a shotgun blast Barney's on the floor
No more Purple Dinosaur

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