Are you referring to the Basic panel in ACR 7.3? If so, what is different is ACR 7.3 has a new set of tools using Process Version 2012 and some of the adjustments from the previous process version 6.7 and before) are no longer available.
I thought that was the case. I'll just have a bit of getting used to the new selection of tools. I see if I open older edited images they show the old tools then.