If you go by the numbers, I've had a pretty good run using Typepad, the pioneers of Movable Type and the personal publishing movement we've come to know as "blogging". History teaches us that technologies have a pattern of being replaced while the broader behaviors they encourage live on. Nature runs it's course and only a few platforms can become the dominant players worth using.
Lessons in innovation (and business). Being first isn't enough.
I like the engine that fuels this site because it's simple and I do it all myself and haven't had a compelling reason to make a change. But new management of the engine is likely to mean less care for the engine not more. So at some point, eventually the engine will need to be replaced. People will always need to get from point A to point B. The vehicles we choose to get us there are another story.