In preparation for this year's fundraiser, I've put a good deal of effort into optimizing the speed of CentralNotice banner loading. Under ideal conditions (fast connection, no servers acting up, not many JS gadgets to compete with), it should take less than a second. Hopefully, this will reduce the "banner bump" problem and cause fewer misplaced clicks. For all the gory details see: http://wikitech.wikimedia.org/view/CentralNotice/Optimizing_banner_loading#2...
These optimizations went into place last week and are now live on all wikis. If you have any comments or questions, please email me personally (I don't read wikimedia-l very often).
Cheers, Ryan Kaldari
wikimedia-l@lists.wikimedia.org