Check Your Speling
It's time to take a break for a little story. Today's story is about how WordPress.com learned to spell.
Several months ago, when we started up this blogging site for y'all, it was an invite-only affair. This little scheme allowed us to manage the growth rate and build up a bit of hype around the 'net. It also let us seed the ranks of WordPress.com bloggers with the people we knew would be strong pillars, for we knew that upon the backs of these giants would be built the towering WordPress.com community.
Sounds kooky, doesn't it? Well, it worked. Here you are, the blogging elite. 
One of my first invitees (we'll call him Clymer to protect his identity) was a distant friend who liked to write everything in a word processor before pasting it into WordPress. Many of you already know what a terrible experience that is. Clymer was not deterred.
When I would ask my friend Clymer why he insisted on using his brand-name word processor despite the horrendous HTML it produced, he always blamed his actions on the lack of a spellchecker in WordPress. Given the choice between a blog visually wrecked by bad HTML and a pretty blog marred with misspelled words, Clymer opted for the ugly blog with good spelling.
Does Clymer's story sound familiar? I've been reading and responding to feedback. I know the score. Just like Clymer, many of you wanted to do all of your editing in WordPress but you couldn't because you required a spellchecker. Friends, your spellchecker is here and I'm going to show you how to use it.
The Button
There is a new spellchecker button in the WYSIWYG editor toolbar that can be activated by clicking on it or pressing the Alt-N key combination. (It's Ctrl-N on a Mac.) After a short delay, any words not known by our dictionary server will be underlined in red.
The Mistakes
At this point, the spellchecker is waiting for you to click on any of these words. When you do, it retrieves a list of suggestions and presents them to you.
The Suggestions
Click the one that you want to replace the misspelled word. When you're done with the spellchecker, you should turn it off so the red-underlined words are returned to normal.
The spellchecker does have some limitations. You cannot add your own words to the dictionary at this time and we do not have such a feature planned. (We will be updating the global dictionary, however, because it's just not right that it doesn't know the words "WordPress" and "blog.") There are also some older browser versions that are not fully supported by this new feature, specifically Firefox 1.0.7 and lower. Also, as evidenced by the title of this post, you can't spellcheck the title field.
Along with this glamorous new feature, we have provided an updated version of the WYSIWYG editor that fixes several bugs and changes the way some things are encoded. Anyone who has struggled with writing code directly into a post will appreciate that the editor is now truly WYSIWYG. <em>See?</em> If you want italics, use the Italics button (or its hotkey). The HTML editor is still available, of course.
Finally, we would like to mention that this feature is on the roadmap for version 2.1 of WordPress, the open-source package upon which WordPress.com is based. Don't thank us, though. Thank Clymer. He's been nagging me for a spellchecker since the day I emailed his invitation.