I moved to WordPress 2.6 in an attempt to fix my Twitter badge being so unreliable. Also I wanna play with the WordPress iPhone app. Here’s my upgrade worklog…

• found that my cache directory, used by MyTwitter’s SimplePie instance, had become owned by “nobody” and could no longer be deleted
• deactivated all plugins, most notably wp-cache
• uploaded virgin WP to a the web server
• moved previous wp-config.php,wp-content/uploads, google analytics secret file, favicon, and h2o theme to new WP directory
• renamed old and new directories so my docroot is now the 2.6 install, and the un-deletable folder is isolated
• ran wp-admin/upgrade.php
• downloaded and installed updated plugins
  • FlickrRSS 4.0
  • wp-cache 2.1.2
  • MyTwitter 1.6 beta
• added some javascript to h2o’s FlickrRSS block so that the plugin itself doesn’t have to be modified to use the Lightbox feature.
• MyTwitter was still behaving unreliably. Tinkered around and decided to remove the bundled SimplePie and instead use SimplePie Core
• … but that didn’t help. Still seems like the Twitter RSS feed being fetched – and cached – sometimes contain no items. Or just one item. I think the issue could be caused by a change in how Twitter responds to feed requests, and/or how SimplePie handles this.
• added some error handling to mytwitter.php, modified the plugin slug and renamed to folder to ignore update prompts
• even with wp-cache re-enabled (expires after 60sec), the new cache directory now remains under my ownership – MyTwitter issue (SimplePie cache expires after 900sec) probably not related to file rights.

Will have to keep poking at this until I find a solution. Then again, Twitter is known for failing, so maybe this is appropriate ?

UPDATE: I am now convinced the problem with MyTwitter comes from SimplePie. I de-activated SimplePie Core, wrote a custom parser/cache-manager with roughly the same interface (but using Twitter’s JSON feed instead of RSS), and tweaked MyTwitter accordingly. Let’s see if that does it…