Ken Thompson says don't worry.

Ken Thompson, a British botanist and writer, says that while plant names are all being changed around because of DNA, we shouldn't let it worry us. He thinks now they have it all sorted and the names won't change again. I'm not so sure, but it's a good article:

http://www.telegraph.co.uk/gardening/8264847/Dont-judge-a-plant-by-appearances.html