One of the biggest reasons tomatoes from the store taste so bad is that they're picked completely green. The second is that the commercial varieties are bred to have a pastier texture and be tougher to stand up to shipping. The third is that tomatoes don't stand up to refrigeration without a change in texture.
My uncle grows tomatoes commercially in southeast Tennessee. If you actually let the commercial varieties ripen all the way and don't refridgerate them, they're pretty good. They're better than the anything you can buy at a fancy grocery store. They're not as good as homegrown brandywines, but they're on par some of the popular hybrid varieties, and will beat out any store-bought heirloom (e.g. a store-bought brandywine).
However, when any tomato is picked to sell in bulk, they have to be picked completely green. Otherwise they'll be too badly bruised to sell. The "vine ripened" tomatoes you buy in the store just means that they cut off some of the vine along with the green tomatoes.
The site is down, so forgive me if I'm pointing out something that's mentioned there. At any rate, in my opinion, commercial tomatoes suffer more from being picked completely green so they'll survive shipping than anything else.