Sky dimension

The Sky Dimension (otherwise known as the Floating Island Dimension, sometimes referred to as heaven) is a work in progress by Notch. It "performs well, [but] looks ugly". It is now a confirmed update, although it probably won't be implemented in 1.6.

The Sky Dimension was first announced after Notch played Spleef against @Evil_Notch (video is on twitter). It was probably made to be like a "heaven", since the "Evil Mojang" team declared the Nether to be "hell". The sky dimension was not completely confirmed until Notch released an update via Twitter stating: "And because PC Gamer made such a big deal of the sky dimension, I guess I'll have to finish it. Consider it confirmed."

Other info

 * It is currently unknown whether or not the "Sky Dimension" will have any of its own items or mobs, although the pictures at this point seem to suggest that it will not.