The pink one is Arcee and the blue one is definitley Chormia -- as confirmed in the toy box art. I'm unsure about the purple one, but I think it could be Elita-One. The rumor is that they transform together.
Arcee was supposed to appear in the first Transformer movie, but got cut because there wasn't enough time to go into the whole female robots explanation. It looks like she has gotten a complete new look in the sequel.