Not that it's really that bad for you per se, but in some way it's even worse than soda because at least when you drink soda you know it's shit. And V8 tries to pretend to be something it's not.
There's not one word on their website about preservatives and it being from concentrate - i.e. they're trying to hide it. You can't get a serving of vegetables from a bottle or can. The same company who makes canned Campbells soups isn't going to all of a sudden proliferate health and well-being to your local corner store.
They get the shittiest fruit and vegetables in bulk because nobody could sell them otherwise, add some crap and make soup.
I don't mean to dog on the above poster but if we all get into the habbit of saying "well it's better than nothing" then we're only going to screw up our diets. Fruit and vegetables should be eaten as they are and if you can't - then skip a serving. But don't rely on V8, they're assholes.