We done goofed. One of the security fixes for WordPress 3.0.5 was overzealous. It fixed the issue, but it also stripped advanced HTML (on display, not save, thankfully) from comments by people with the
unfiltered_html capability. It’s sort of a rare bug — doesn’t apply to multisite installs, and not many people know that Editors and Administrators on single WP installs can use images etc in comments, so we don’t think it warrants another release. People have WordPress 3.0 fatigue already. And 3.1 is so close I can taste it (takes like pork BBQ, natch). But it is still annoying.
As Nacin mentioned, a hotfix for this issue went into Akismet 2.5.3. Akismet is very popular, and just happened to be planning an update today. We figured that would be an easy way to fix the issue for some WordPress users today. The Akismet team at Automattic was kind enough to oblige.
But this wasn’t the first non-critical-but-sort-of-annoying bug in WordPress, and it won’t be the last. So I created a plugin: Hotfix. It fixes the 3.0.5 bug, but I intend for it to fix selected future bugs as well. If we can get this installed on a bunch of sites, it could be a very handy way to push fixes out to people faster than we can with WordPress core releases.