If Soylent got popular enough, it would pretty much make my service obsolete. I doubt that'll happen anytime soon, but I'm still a huge supporter of what Soylent is trying to accomplish with taking the thinking out of what I should eat. You can actually use the two in conjunction pretty well by adding Soylent as a "custom food" on Eat This Much, making it take up about 80% of your daily calories, locking it in place, and then running the meal plan generator to fill in the last 20% of your calories with real food.
Here's an example where I added Soylent similar to one of their initial recipes, each serving being 1/4 of their daily recommendation (and a higher calorie target so I don't atrophy into nothing): http://www.eatthismuch.com/diet/802429276