Ds (now 9) wasn't reading at age 6 either, and I was also freaked about what that was going to mean for classes he was interested in. I did some research and realized he was more inclined to sight words (he could identify huge dinosaur words, but words like 'the' and 'was' had absolutely no meaning attached to them, therefore they just didn't register). He is a visual-spatial learner ('right-brained'), and once I realized that, I also started to understand all that he was really capable of, reading-wise. So no, he didn't sit down and 'read', but if he needed to know something, or was looking at a book, he could pick out big words that were meaningful to him. So fast-forward to 9, and he is an unstoppable reader. We never forced the issue, we just kept answering his questions ("What does this say?" etc.) and filled in phonetic gaps when needed. So now he actually does pick up books and sit down and read. He is still more inclined to graphic novels, and other books that have visual clues. Lately he is into the "Warriors" series by Erin Hunter: Dh reads him the novels at night, and ds has some of the mangas and reference books that he reads himself during the day. It is soooooo exciting to see how the process has unfolded.
So I second what a lot of others have said. Make certain it doesn't become a battle, look into her learning style, and just keep reading to her! It will happen!