Mach-II rocks. It is one of the more "mature" surviving ColdFusion application frameworks, and as such doesn't get nearly the amount of buzz that the new (interesting, different, creative, awesome-in-their-own-way) frameworks get. If you're looking at frameworks, I encourage you to take a look at the amazingly capable Mach-II - we've had fantastic success with it!
Things I really, really like about Mach-II:
Take an old (Mach-II 1.1 app, circa 2006) and update the framework to 1.8 (released 2009). Replace the application.cfm file with application.cfc, comment out everything in index.cfm and *boom*...you're done. I can't really assess how challenging it is for the team to maintain backwards compatibility, but I sure do appreciate how simple it is to upgrade. Instant feature add with zero headaches.
and in your listeners:
I don't think it gets much easier than that. Instant Coldspring integration for dependency injection (and more), radically simplifying the configuration of all of my listener and model cfcs. Now we've got all the power of Coldspring cleanly available to our Mach-II application.
Knowing where to find things is one of the hallmarks of any good framework. Some do it by convention, some by configuration. Mach-II falls into the latter camp but that's perfectly fine by me. Getting back into the mental model of an application months (or years) after deployment is a challenge but by simply cracking open mach-ii.xml I can see what happens where within seconds and bend it to my will. I love this.
This wasn't in the framework back in the 1.0 and 1.1 days (when we created some mammoth apps), but by 1.5 (which came out in 2008) the ability to break up large Mach-II applications into separate modules was baked in and oh-so-handy. It's two years later and we've been able to make the easy changes to break those older apps into a collection of modularized sub-apps for much easier maintenance. Perfect example is an extranet: lots of only slightly related apps put under one common umbrella sharing security or UI components. This is easy to implement and support in a well-designed Mach-II application. All of our more recent apps make use of this feature.
The people who created and have since improved and evolved Mach-II are some of the smartest folks who are or have been involved in the ColdFusion community. Look at this list. Not only have they created something awesome, but they're incredibly responsive on the wiki, development Google group, and framework users Google group. They use this framework at their day jobs so you know that each release has been painstakingly designed, implemented, tested, re-tested, piloted and then released. Plus, they're open to new ideas (even if you personally have no idea how to make them happen!). Code is great, but the people are the best.
This is where some of those "convention-based" concepts have crept in to Mach-II much to the benefit of the users. Back in the "bad old days" your mach-ii.xml file would contain a block that looked sorta like this, except far longer:
Each page would have a page-view defined. Someone called shenanigans on it and now we have the PatternViewLoader to replace ALL of it!
So, so simple. Love this line of the config file more than any other.
Take Mach-II off the shelf and use it as your "glue." Add Coldspring to manage your model. Use ColdFusion 9's new Hibernate ORM capabilities to cut the lines of code in your model by a huge factor. Redirect some of the saved time into building a better UI using jQuery, improving your cross-browser capabilities with clean CSS and making your client happier by communicating more frequently. Result: a better app, designed to be maintainable and much more in line with your client's spoken and unspoken expectations. How could any craftsman not feel good about that? Mach-II is a key component to that successful formula for us.