I have the impression that Delphi isn't very popular anymore. But now at work I had to make some changes to an old Delphi program that we are still using. I used Borland Developer Studio 2006 and it was very pleasant and intuitive to work with, even though I had practically no previous exposure to it. Is Delphi still widely-used and I am simply not aware of it or are there other reasons for its decline? 
Delphi is still around and very much alive, but under new ownership.

Borland really lost their way.  They had a really large product line, and the main thing that people were interested in was Delphi, but what the PHBs thought was going to be big was not their development tools, but their Application Lifecycle Management tools.  So they put a lot of resources into developing and promoting that instead of Delphi, and let the development tools branch languish.  I even heard from some former Borland employees at the Delphi Live! conference a few years ago that their sales people were actively discouraged and dis-incentivized (is that a word?) from trying to sell Delphi at all, even to potential clients who expressed interest up-front.

A few years back, things changed.  Borland sold their entire development tools division to Embarcadero Technologies, which up to that point was mostly known for database-related software.  Now their big claim to fame is that they're the guys who make Delphi.  Within a few months of the sale, Borland stock fell below $1/share and they were bought out by a "corporate graveyard" company that basically does nothing but manage licensing fees on existing products. Borland no longer exists.

Embarcadero, though, actually cares about Delphi.  They've put a lot of work and effort into it, and the product quality has improved tremendously in the last few releases.  Despite both the recession and Delphi being a commercial-only tool in a perceived "age of open-source development," sales have been really strong and the team's been able to make a lot of progress.

TL;DR: Borland is dead; Delphi is not. It's "Embarcadero Delphi" now, and it's very much alive and kicking.
