Yeah, I've noticed this to. I bought the keyboard dock a few days prior to the iPad 2 launch (yupp, I'm stupid. But I can afford my behaviour ). Fingers crossed that the iPad 2 will fit in the "old" keyboard dock...
I was thinking this exact thing earlier today. Apple eliminated the keyboard dock, and are actively showing the Bluetooth keyboard as an iPad 2 accessory. One would think they would update 4.3 to better take advantage of all the buttons. I wonder if anyone can try it with 4.3. If not, it is certainly something they should "button up" (pun intended)