The latest incarnation of Delphi (the tenth version) 2006 seems to be way beyond the microsoft contribution to the field. Out of the box it provides a massive component suite and extensive refactoring tools.
I have just upgraded a large Delphi 5 application suite to D2006 with very little pain.
A few objects had moved units, I had to add the variants unit in a lot of places. Some of the MIDAS parameters now expect TCustomClientDataSet rather than TClientDataset.
It is impressive in that I was able to interchange COM clients and servers build with the differing versions without much trouble. In fact the code areas which we had used the built in events the least required fewer or no changes.
A minor annoyance is that the TChart was missing from the QuickReports 4 suite.
TeeChart is an amazing chart control suite.
Developer Rants 