Not so fast with the "first"
"first merging of previously separate development environments"
Nope. The only "first" involved is the first time that new standalone Delphi and C++ Builder versions have been released simultaneously.
Delpih and C++ Builder used to be separate products with separate release schedules.
Then Borland combined them in the multiple-language Borland Developer Studio (latterly RAD Studio), incorporating Delphi, Delphi.NET, C++ and C# all in ONE IDE.
Then the Turbos were created as individual language versions of BDS, separating them once again for the Turbo line.
Delphi 2007 and C++ Builder 2007 were released at different times once again, but RAD Studio continued to offer an integrated, multiple language IDE (Delphi, Delphi.NET and C++ - C# support became a little limited however).
With Delphi 2009 and C++ Builder, what is being released are the INDIVIDUAL, stand alone single language IDE's. What is different this time is that (apart from the Turbo's) this is the first time that BOTH otherwise separate products have been released at the same time.
C++ Builder historically used to lag behind it's Pascal cousin.
The fully "merged" product - RAD Studio - will as before be released later, presumably including an update to the Delphi.NET personality that it includes in addition to Delphi and C++.
Hopefully that clarifies things.
("Yep, clarified as mud")
Mines the one with the Pascal in the pocket.