I have mixed feelings about Delphi.
It evolved from Pascal, which as languages go for teaching was actually pretty good. I did Pascal in high school but I had already cut my teeth with c++, so it wasn't my first language.
Delphi took Pascal and made it into a RAD kind of thing, so it has the same syntax but a lot of the actual nuts and bolts are hidden away from you. Useful for if you want to knock together a GUI for some kind of database application in a day or two, not so useful IMO for teaching the basics to CS students.
Hmm to be pedantic, Pascal is the language and Delphi (and Lazarus) is the environment. Like C# and Visual Studio. As an environment, Delphi is not that bad, but I just find the Pascal language very verbose, clunky and cumbersome. The whole interface/implementation sections thing is a massive pain. It gets in the way of creating code and interrupts the train of thought all the time.