Now, I'm not saying that there's no point to the whole organic business, but take a gander at this:
The Omega 6:3 fatty acid ratio is often cited as a reason that grass-fed beef is healthier than grain fed. This analysis shows that there's so little omega-3 in any sort of beef that if you're truly relying on it for your omegas, you're going to get nowhere. Sea food may be more important when you're eating grain fed, but this isn't that great of a reason to choose grass fed.
It also strikes me as odd that I read somewhere else that a grass fed but grain finished (i.e. fed grain towards the last few weeks before slaughter) would revert to the omega ratio of grain fed. So, is that saying that all that time growing up on a healthier diet did not produce a healthier cow?
Well, not exactly. This analysis only proves that the omega ratio doesn't matter. What still seems irrefutable is that grass fed meats have more vitamins and minerals. Butter from pastured cows? High in all those essential fat soluble vitamins, A, D, E, and K. If anything, it's more important to fry your eggs in pastured butter than eat pastured beef, but that's a personal decision. (There's also the decision as to whether you want to support the inhumane practices of family farms. But, in the great scheme of feeding the world, not every cow can be pastured, and cost is a factor. It's good to know you aren't costing your health too much if you can't afford grass-fed.)
On the veggie side of things, here's a post on organic produce:
The article states that organic produce is still often produced with toxins, they're just organic toxins. Some inorganic toxins are engineered to decompose quickly, meaning that organically farmed produce may have more toxins when it gets to your plate than its counterparts.
The same still holds that organic often beats the run-of-the-mill varieties in nutrient composition, but far more important is the freshness of your vegetables. A vine ripened tomato beats one that was picked early, often regardless of whether the soil was mediocre or not. Freshly picked spinach has double the folic acid as spinach that's been sitting there a week. So eating in-season is more important than organic, and often cheaper. Frozen veggies also have their nutrients packed at the moments they are highest, so there's no distinct health reason to go for fresh (and so often wilty) over frozen. (I do have to say, farmer's markets beat all in terms of taste, at the very least! I love the farmer's market.)
Just some food for thought.