I noticed on my wordpress blog that the RSS widgets were really, really slow to update. I wanted a news section or to display articles from one of my other sites but they took so long!
Here is the solution:
The default frequency with which the RSS widget updates is apparently every 12 hours (http://www.village-idiot.org/archives/2009/08/04/fix-the-rss-update-time-on-the-wordpress-rss-widget).
How does one change that?
By adding the following code to the function.php file of your current theme:
add_filter( 'wp_feed_cache_transient_lifetime', create_function('$a', 'return 1800;') );
The number “1800″ represents 1800 seconds or 30 minutes.
I did this and it worked fine!
Let me know if you have any problems.
*UPDATE* Here is a post that explains the nitty gritty of this a little bit more: http://casabona.org/blog/2009/08/07/qt-increase-the-wordpress-rss-widget-refresh-rate/
Hat tip to Ahmed for finding this more thorough information!