Your point is well made, and I have taken note!
There have been plenty of "upgrades" or "new versions" to be sure, as is very often seen as a necessary part of a proprietary software business model and, as such, not necessarily real evidence of a "maturing" product.
After all, revenue must continue to be created, and there is only so much growth potential available. It may well be a sign of true maturity, but can also be a sign of constantly changing direction and planned obsolescence of "older" technology to drive "upgrade" revenue. How you view all of that, and the particulars of CF, is very much a matter of personal perception, taste, and needs.
All that said, CF is still proprietary and, as such, has been totally defendant upon first Allaire, then Macromedia, and now Adobe.
At any time Adobe could either discontinue the product, reposition it dramatically, release yet another "new and improved" version (that may, or may not, necessitate an upgrading of server support), or sell it to another who could do any/all of the same. What a disaster it would be if DreamHost's business model suddenly found itself at odds with the direction a proprietary product, to which they have "hitched their wagon", decides to take.
Part of what makes DreamHost such a great value is them not having to wrestle with rolling "upgrades" of proprietary software and their ability to tweak and tune code as needed to meet their needs.
I don't see this discussion so much as a "pro-CF" vs "Anti-CF" argument from the users' perspective - different people like different things. I just hate to see DreamHost embark upon such a path, as it would drain resources (money, people, and time) from providing basic and essential hosting services. I also wonder where it would stop? Next thing you know, folks are clamoring for .ASP support, etc.
All those technologies have their place, and there are plenty of hosts out there for those that want to use them. As it is, DreamHost is a rare "clean well-lighted place" that provides a unique value - I think their commitment to FOSS software and the general rejection of proprietary technologies is part of that, and part of what allows them to provide the value I enjoy.
People that want CF should definitely use it, even vote for it to be implemented on DreamHost if they don't want to use a CF host, but those of us that don't feel it is a "Good Thing" (tm) also should definitely let our opinions be known.