the one time we took our kids. they were about 1 and 3. The show entertained them both the whole time. But my cousin's son could not sit through it and he was almost 4. I think it depends on the child.
Can your daughter sit for an entire movie? If she loses interest in things quickly, you may want to wait until next year. But if she likes sesame and she'll sit that long, I say go for it. It was alot of fun.