What made this problematic was the fact that there was no option to turn it off or at least suppress it. As soon as you opened a chat a read receipt would appear on the sender's screen.
The only option to avoid the read receipt until now was to not open the conversation in the app.
A new update has been released on the official website that fixes the issue. Note that it is only available on the website and not on Google Play or another app store at the time of writing.
If you are using WhatsApp and want to get rid of read receipts then your only option right now is to download the latest version from the official website and install it manually on your device.
The version that introduces the new preference is WhatsApp Messenger 2.11.444. The easiest way to install it is to point a mobile browser to this page on the official website and download the new version from there.
Once it has been downloaded tap on the download and follow the installation instructions. This works like an upgrade if WhatsApp is already installed which means that you won't lose any chat history, contacts or your subscription.
To disable read receipts
Tap on the three dots icon in the top right corner and select Settings from the context menu that opens up.
Select Account under Settings and on the next page Privacy.
Scroll down until you find read receipts listed there.
Remove the checkmark and you are done.
This turns of read receipts on both sides meaning that you won't get read receipts for your messages and that others won't get them for messages they sent you.
There is also no option available to turn off read receipts for group chat. According to WhatsApp, those are always sent out no matter what.
This is definitely an appreciated move even though it is still not clear why the preference was not available when the read receipts feature launched.