Okay, maybe not world domination. But at least significant progress toward truly usable, community-developed software. Drupal and WordPress are hitting their stride right now. It's getting easier to build sites on a budget that orgs can mostly manage and update themselves. That's a big deal for our sector. These platforms allow our web communications to keep pace, at least somewhat, with the rest of the business world. We have to get our messages out, amid the clamor, just like everyone else, and the playing field is getting more level. Yes, we might be a bit behind in our ability to afford all the bells and whistles, but with a Drupal or WordPress site, we can blog and integrate with email messaging, Facebook and Twitter. If we know our audience and have a clear message, that's all we need in our toolbox right now.
I was working almost exclusively in Drupal for a while, and now I'm diving back into WordPress as well. Sometimes it's simply the best CMS for the job. It had been a few years since I'd last built a WordPress site, and it's come a long way. For small- to medium-sized blogs and simple websites, it's incredibly easy to build in. For content editors and site admins, its back end admin beats Drupal hands down in several areas. Of course Drupal's back end can be completely customized to be more user friendly, but when an org is on a tight budget, WordPress has much of that ease-of-use right out of the box. If all you want to do is manage a fairly simple blog or website via a browser, WordPress is stable and flexible, and more than enough power for many orgs' needs.
One of the best summaries I've ever read of the differences between WordPress and Drupal, and of how to decide which CMS to build in, is WordPress vs. Drupal... Fight!  by Michelle Murrain. Here's a snippet:
Kinds of sites probably best done in WordPress:
- Community Blogs
- Simple brochureware websites
Kinds of sites best done in Drupal:
- Large community sites where you need different kinds of content generated by users (blogs, wikis, job postings, etc.)
- Complex, document-heavy library sites, or sites that need document management
- Sites where you want complex control over multiple content types – how they are created and viewed
- Magazine/Newspaper like sites where you want to control how lists of content are displayed and ordered
- eCommerce sites
- Sites with deep integrations to CRM platforms and web services
Kinds of sites where it’s a tossup:
- Medium or large websites with lots of content, but relatively simple organization
- Community blogs with many authors and identified, authenticated users