There are clear reasons why Domino remains, technically, a better platform than any other. I'm serious, too. There are weaknesses in Domino, yes, but they don't hold a candle to some of the silliness that passes for server software in the world today.
Now, mindya, I've seen platforms come & go since 1980. I'm in the business ... forever, to young developers. My first encounter with software silliness came during the 4GL and o-o crazes of the 1980s: you've probably heard of one, and not the other. 4GL produced SQL, but was generally a failure. o-o produced ... well, modern programming languages, and was generally hailed as a success.
Yet we still have similar problems with software and its development today.
It was with this jaded experience that I took my experience with both these, and spacecraft telemetry and controls systems into my first programming encounter with Lotus Notes -- or as the server is known now, IBM Domino.
It seemed immensely arcane when I first programmed to Notes in the early 90's. However, I realized quickly how useful the system was. Applications, however arcane and custom, were relatively small, and were quick to complete. It was completely backward from the way I had learned it -- arcane stuff's supposed to be too slow to program. But it wasn't.
Later versions of Notes & Domino made the arcane programming simpler. The object model clarified and crossed language boundaries -- and was particularly unpleasant in Java due to some early mistakes, but has been overcome recently by the sophisticated, longstanding developer community (see http://openntf.org for more info) . But I was constantly captivated by the wonder over why my original encounters with the arcane C API in Lotus Notes, why that encounter went so well.
It was the data structure.
The Notes data structure inspired object-oriented database designs before they existed. It's reiterated in document models throughout Web browsers and servers today. And it's simple and straightforward to expand whenever the developer finds the need: supporting upgrades, or architecture changes, or ... really whatever the developer needs.
SQL admins will remark in disgust at this point.
But data structures and file structures developers, take notice: the data structure is quick to develop.