I've used Drupal and Wordpress extensively before...
Wordpress... too... messy? contains a lot of code, hard editing themes/templates... had to "Hack" it... but then couldn't really (was scared to) update it, because my hacks might break... so didn't really keep it up to date. (Which gotta update it like every couple weeks... come on!) But it was too popular, so scared it wasn't secure if don't update it...
and can you say spam? It's the "Windows" of the CMS world...
Drupal... hackers wet dream? What can you do with it? (What Can't you do with it!) But... you can do too much... it's not easy to do easy stuff... everything is programmed correct... hundreds of classes and modules... it was too "perfect"... hard to do everything, but I can see how programmers could enjoy it... but you got to love the project you are creating with Drupal... it'll be a custom job.
Rolling out many Drupal sites and maintaining them could be trouble... it's hard to make things perfect... and my gosh all the options, fields, parameters, and customization... fields oh my. It's like the "Linux" of the CMS world...
Then there's MODX... I've only been using it for a short period of time right now... but everything seems to be sweet as sauce... Has a very small footprint... I love the default theme...

which as you all might know, it's nothing!
Simple yet powerfully expressive... kinda reminds me of the Python programming language. You got your Templates, Chunks, Snippets, TVs, and Plugins... seems like this is all you need... no messy fields to mess with... unless you want to.
It could potential be the "OSX" of CMS world... still great for developers (like OSX is, which has roots in FreeBSD) Simple yet Powerful. It let's you do things exactly the way you want to do it. No excess, no waste.
With better installation... easier way to do menus / blogs and maybe a little better interface, (It already has a killer back-end, and conceptual) it'll BE the "OSX" of the CMS world.