Image of duckweed
The plant, which seems to be new, was not developed as a source of B12, but rather as a means to do control blood glucose.
A huge red flag for me is that the company claiming this great advance
is based in South Florida. Why should that be a red flag? I lived in South Florida for 15 years, and it is one of the scam capitals of the world.
Still, it's not impossible that this product will turn out to be real and will be a plant based source of B12. B12 is produced by bacterial action, so it's not impossible that a plant could contain B12, just none haven't until now.
Humans actually make B12 (or bacteria in their large intestine do) but the only thing that happens to stuff in the large intestine is that it gets eliminated.
The duckweed in the image is not the variety grown by Parabel (the company that is growing it), which is a variety known as Mankai. Duckweed is a broad descriptor of the plants that grow along the edges of any pond. I was surprised to find an image of it on Pixabay.com, to be honest.
So does this change my opinion of veganism? No, not yet. Unless and until Mankai duckweed comes to a local market and can be eaten as food, then veganism still requires supplementation.
My read of the slim amount of information available (basically everyone used the same press release
to write up the story) is that the company intends to produce supplement powders rather than sell the plants. A supplement is still a supplement and shouldn't be necessary for a healthy diet.
That having been said, a powder that could be added as a spice to dishes, soups or smoothies would be closer to actual food. It's early days at this point, too early to make a final determination.