Yes, it's best to use nutritional yeast for savory foods. It really does bump up the umami flavor pretty well, and I think it tastes good, but I actually use it more for the flavor than for any nutritional aspect. Common uses in my kitchen:

- Using it with salt and water makes a kind of chicken broth'y flavor. - Butter or margerine on toast, then sprinkle nutritional yeast on top. Doesn't sound like it'll be good but a friend introduced this to me and it's one of my favorite snacks. - Add to tomato sauce for a "meat drippings" like flavor. For an easy and cheap spaghetti bolognese use TVP, nutritional yeast, a dash of tarmari, and your usual tomatoes and oregano and basil. - Of course, a lot of people use it as fake cheese... you can make a "nacho cheese" type flavor out of it easily

Tons more uses.