They remain standard for informal writing, especially when short, closely connected clauses are being spliced. There is nothing inherently wrong with a comma splice, although when overused or used by a tin-eared writer, they can sound like run-ons.

Is a comma splice wrong?

It is incorrect to join two independent clauses with a comma. This error is called a comma splice. For example: I went to the mall, Jane was there.

Are comma splices ever OK?

Comma splices are also acceptable in fiction. In dialogue and first-person narration, for example, a character might be excited or upset and thus speak in a rush. The minimal pause conveyed by a comma can clarify sentence structure while conveying the character's state of mind.