Version 2.5.6 of the Akismet plugin for WordPress is now available. This is a maintenance release that includes several bugfixes and improvements to performance and robustness:
- Prevent retry scheduling problems on sites where wp_cron is misbehaving
- Preload mshot previews
- Modernize the widget code
- Fix a bug where comments were not held for moderation during an error condition
- Improve the UX and display when comments are temporarily held due to an error
- Make the Check For Spam button force a retry when comments are held due to an error
- Handle errors caused by an invalid key
- Don’t retry comments that are too old
- Improve error messages when verifying an API key
To upgrade, visit the Plugins tab of your wp‑admin dashboard and follow the instructions. This version of the Akismet plugin requires WordPress 3.0 or higher. If you haven’t already upgraded an old copy of WordPress, now is a good time: the new plugin release will provide significantly more accurate results than the legacy plugin available for WordPress 2.x.
If you haven’t yet activated Akismet, you can sign up for an API key here. Personal blogs and sites can choose how much to pay, starting at $0.
Akismet 
“Preload mshot previews”
LIKE!
Just updated
wtf… akismet_counter code not working
All of the reports we’ve seen for this are for hosts still using PHP 4. WordPress and the Akismet plugin both require PHP 5.2 or higher.