heirlooms or hybrids, which is best?

Kudos to the New York Times and yesterday's article on this topic - very informative and I think, fairly balanced.  Okay Michael Tortorello you get back a little bit of my respect with your non-judgemental reporting on this topic.  You know I have not been such a fan in the past.  Maybe you and I will be turning over a new leaf this gardening season....

My favorite quote from the article is, "Heirlooms are not intrinsically more appetizing than modern hybrids. Heirlooms began as hybrids, after all — a fortuitous cross of two parents. Modern hybrids, or so-called “F-1s,” are usually proprietary to a seed company. But this is still the 19th-century genetics of Gregor Mendel, not genetic engineering."  In fact, at many of these seed companies, even the big ones, they are cross pollinating varieties using real high tech gadgets, like Q-tips to mix up the pollen.  Seriously.  It's about as far from a GMO as you can get. 

In case you care, about 20% of my seeds come from Baker Creek Heirloom Seeds (and their new branch, Comstock, Ferre here in Connecticut) and 80% come from Johnny's Selected Seeds, both highlighted in the article.  And for the sake of clarity, Johnny's also carries heirlooms.  The vegetables that I choose to grow as heirlooms for the most part are tomatoes, beets and swiss chard.  The rest are hybrids.

Which are hybrids and which are heirlooms?  Can you tell the difference?