My little guy was getting lazy and not latching well w/ just one bottle in the middle of the night. We were using Playtex and natual nipples. So, I went on a quest to find something new. I felt it was too early for him to seem to start preferring a bottle over me. So, I found a new bottle by Evenflow. It is called the Elan. It has a much bigger circumference than all the other bottles and the nipple is bigger. It is more like a natural nipple than the others too.
I noticed a change in his latch and suck immediately. It has been over a week now and it still feels like we just started all over again!: His suck is so strong!
I found it at Target. Babies R Us does not carry it yet. I did find it online at Wal-Mart also. They list it as a new item so I can't say if it is in the stores just yet.
Also, this bottle grows with the little one. The top fits their pump, has a bottle top/nipple adapter, and then later becomes a sippy cup.
Hope this helps! It is working wonders for Nicholas and I.