I believe it as windows 2003 thing. I don't have the next button avaiable on any of my win7 machines with RSAT installed. However, my coworker installed adminpak.msi and has the next button feature when creating a new computer object. Makes it a little hard to prestage though.
Nevermind, I just ate my words. I went to add remove features on a w2k8r2 member server and install the AD DS tool set. I opened up AD users and computers and low and behold, there was the next option.
Can't explain why they doesn't appear on my win7 box with RSAT....