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Most dictionaries and many academics regard it as non-standard because of the double negative aspect, but its use is widespread — particularly in spoken English.
Thankfully, this is rarely heard in the UK. I will be very unhappy if it ever becomes so widespread here that it's considered non-standard but acceptable.
Certain members of this forum take the view that if it's listed in dictionaries (which it is), it must therefore be considered correct and acceptable usage.
I'm not quite sure what 'non-standard' means when it comes to word usage.