The latest update in WhatsApp is showing blue ticks when your message has actually been read. Two grey checks only mean your message had been correctly delivered to the recipient, but that doesn’t imply it had been read. And as you may already know, a single grey check mark next to your WhatsApp message says that the message has been sent to the recipient.
So, from now onwards with this blue double check confirmation next to your WhatsApp messages sent, one can no longer say the excuse that they haven’t read your message.