Q:  Which memory model does Delphi use?

A:  Delphi uses a mixed memory model.  The defaults are:

  - Methods are far
  - Procedures in an interface section are far
  - Procedures only used in an implementation section are near
  - Heap data and all pointers in general (including class instances)
    are far
  - Global variables are near (DS based)
  - Procedure parameters and local variables are near (SS based)
  - Procedures declared FAR or EXPORT are far
  - Virtual memory tables are far for the new class model and near for
    the old

This scheme has been used by Borland Pascal for a very long time. I find it flexible and efficient.

Since all public procedures, methods and pointers are 32bit already, Delphi32 won't have to change any of that.  It's likely that Delphi32 will switch to 32bit addressing for the data and stack segments too, but that shouldn't affect any of your code either.  What will affect it is the change of Integer from 16 to 32 bit.