Ok, so i read over all of the posts and I wanted to give my opinion, only my experience for that matter. I breast-fed and supplemented with formula both my children (now 6 & 4). The were on a bottle briefly, until about 5 months old and then had any fluids other than breast-feeding in a sippy cup. I think your daughter is indicating to you she is willing and interested in trying a sippy cup. It was our decision not to have bottles bacause I could not stand to watch a baby walk around with a bottle hanging in their mouth (just my own preference). And I did not want food/ milk to become a comfort issue.
About the whole milk verses formula thing. Both my children went to whole milk at 10 months with my pediatrician's approval.
In my humbly opinion, I feel the formula companies are selling a product and their main goal is to sell that product to you as long as they can, a very expensive product I might add. For example, Nestle went into third world countries and marketed formula to the locals in guise of helping the locals with nutrition and the mothers stopped relying on breast-milk and began relying on formula. This was a difficulty because third world countries often have unsafe drinking water and unsanitary conditions and language translation issues. So the formula caused problems in mixing quantities, using unsafe water, and preparing unsanitary bottles. Google "nestle formula third world" and you can read up on it.
And for those who say babies tummies cannot handle milk; all formulas except soy-based are made from milk. Our mother's generation used to home make formula with carnation dried milk. So if your infant has had regular formula, they have been exposed to milk. And this is not a newborn tummy, this is an almost 10 month old tummy which has been eating all types of foods. As my pediatrician said to me, "there is no magic change that happens from a 10 month old to a 12 month old tummy".
Along the nutritional side, if your baby is eating a well rounded variety of fruits, veggies, and meats and milk (via my pediatrician) they are getting everything they need without the formula. And if your child had a milk allergy, it would already have developed and pronounced itself by now. And if you are really worried, why not give an infant liquid vitamin over giving formula. It is much cheaper!
Again, only my humble opinion. But I wanted you to have one opposing view to all the other posters who had kindly replied to your request.
Talk with your pediatrician, do your research, and then follow your gut. No one person knows all; they can only give your their educated opinion.