Unfortunately there is no single, centralized list with the changes between versions of Delphi.
Here you have a list of links of changes for each version.
- What's New in Delphi 6
- What's New in Delphi 7
- What's New in Delphi 2005
- What's new in Delphi 2006
- What's New in Delphi 2007
- What's new in Delphi 2009
- What's new in Delphi 2010
- What's new in Delphi XE
- What's new in Delphi XE2
- What's new in Delphi XE3
- What's new in Delphi XE4
- What's new in Delphi XE5
- What's new in Delphi XE6
- What's new in Delphi XE7
- What's new in Delphi XE8
- What's new in Delphi 10 Seattle
