Update: Shocker! Mark Shuttleworth has just added a comment to the bug report stating that once issues with Unity 2D are fixed (see bugs #733233, #733431), the theme will be going back to 0px border goodness.
As if to prove our own wisened words of Alpha Caution true, one of our favourite tweaks to the look of Ubuntu 11.04 has been reversed in less than 24 hours.
The borderless ‘light themes’ change we reported on yesterday has been ‘reverted’. Despite being a popular change with the majority of our own readers Ubuntu’s founder, Mark Shuttleworth, deemed the look ‘bland’ and an update to the light-themes package today reinstated 1px borders to Ambiance and Radiance.