We found a *little* baby talk to be VERY helpful early on.

We carried on normal, adult conversations with DD as a baby all the time, and we found that within the first 4-6 months, she started picking up her own words... and they were typically baby versions of the words we were using, because she was struggling with the linguistics, as early speakers do. When she was thirsty, she would ask for "juice," so that was easy, but most of her other words were of the "ma-ma," "da-da," "nite-nite," "tub-tub" variety. We gave her "nite-nite," but we always rephrased ourselves in both baby and grown-up terms: "Awww, are you tired? Ready to go to sleep? To go nite-nite?" "Tub-tub" was something she came up with independently, derived from a silly song I made up for bath time.

As I've mentioned before elsewhere, by the time she was six months old, she had a word for everything she needed, and if there was a word she lacked for something she wanted, she'd just point and say, "That!" and if we still couldn't figure it out, we'd say, "Show me," and she'd get as close to it as she could, still pointing, and we'd pick her up and move her closer to it if necessary (because "that" might be cookies in a high cupboard, or a toy in her bedroom upstairs), until we finally understood what she was pointing at.

The one exception was she still didn't have a word that said, "I'm hungry." When she was 8 or 9 months old this was resolved, when my mom started babysitting on a regular basis, and she'd sit there baby-talking all the way through a feeding, saying, "Mmmm... num-num!" over and over again.

All these baby words made things SOOOOO much more peaceful in our home. And if DD said, "Mama, num-num," and DW responded, "You're hungry?", she was learning proper speech while still being able to communicate her needs. So it doesn't really have to be an all-or-nothing approach.