Migration to MODx Revolution (and HTML5)
My main site (hypercubed.com) has run on MODx classic (aka modx evolution) for several years. I felt it was time to enter the 2010s and move up to MODx revolution. Here is a brief summary of my experience.
Probably the only real draw back to running MODx vs. Wordpress is the upgrades. One click is all it takes with Wordpress. MODx... not so much. I didn't even bother trying to upgrade. Instead I decided to go the manual route. I installed MODx revolution and manually copied content to the new site. Well, I actually used a little mysql magic. I won't delve into this as it basically amounts to a manual copy of the content and chunks (html snippets) from the old site to the new. Luckily my site is pretty small... your results may very. I didn't even bother with the comments on my old site which I would categorize as more abused than used.
The MODx tags (part of the templating system) have changed significantly between evolution and revolution (see here). It would have been pretty simple to just replace the tags and be up and running. However, since I was already in working on the site I decided to make the jump to HTML5. This was made very simple thanks to HTML5 Boilerplate. HTML Boilerplate template is simple and easily customizable. It comes with jquery and Modernizr to ensure backwards compatibility with old browsers (and IE9).
One great thing with MODx is contexts. Using contexts I was able host multiple top level domains using use one MODx installation (and manager login). This might have been possible using MODx evolution but I never tried. Have a look at this tutorial on how to set this up. This is also a great way to have a "hidden" beta site to test changes before going live.
So while the upgrading process has a lot to be desired; MODx more than makes up for it in flexibility. If you are running a non-blog site I still recommend MODx. If you are looking into jumping into HTML5 I suggest you check out HTML5 Boilerplate.