It dominated the scene for quite a while. Looking at the Xyzzy award winners will confirm that. Even the first Best Game winner ("So Far" by Andrew Plotkin) was an Inform 6 game.
However over the past decade or so the scene diversified a lot more, particularly as choice-driven rather than parser-driven games became a lot more popular. Twine is a tool for making browser IF games that really broke through there, although in recent times Ink has gained popularity both for making IF and as a tool for making dialogue systems in other non-IF games. Most new parser-IF games I encounter though still tend to be Inform.
A small tangent: for readers interested in IF and curious about trying to write one, Inkjam is 3-day event where you make a short game with Ink, and this year's event is in early September. I participated last year and it's good fun and a good challenge!
FWIW, I recently found a succinct description of the strengths of parser-based and choice-based IF tucked away as an aside in an article by Jimmy Maher on a different subject [1]:
> a hypertext narrative built out of discrete hard branches is much more limiting in some ways than a parser-driven text adventure with its multitudinous options available at every turn — but, importantly, the opposite is also true. A parser-driven game that’s forever fussing over what room the player is standing in and what she’s carrying with her at any given instant is ill-suited to convey large sweeps of time and plot. Each approach, in other words, is best suited for a different kind of experience. A hypertext narrative can become a wide-angle exploration of life-changing choices and their consequences, while the zoomed-in perspective of the text adventure is better suited to puzzle-solving and geographical exploration — that is, to the exploration of a physical space rather than a story space.
Jimmy Maher's blog on the history of computer gaming, which emphasizes interactive fiction, has been going for years and is a comprehensive (and highly readable) source information of how companies like Infocom and other "adventure game" designers in the 70s and 80s led to computer gaming as we know it today.
However over the past decade or so the scene diversified a lot more, particularly as choice-driven rather than parser-driven games became a lot more popular. Twine is a tool for making browser IF games that really broke through there, although in recent times Ink has gained popularity both for making IF and as a tool for making dialogue systems in other non-IF games. Most new parser-IF games I encounter though still tend to be Inform.
A small tangent: for readers interested in IF and curious about trying to write one, Inkjam is 3-day event where you make a short game with Ink, and this year's event is in early September. I participated last year and it's good fun and a good challenge!