Before the release of the iPad 2, there were a number of rumours that hinted it would get a retina display. This of course didn't happen. The rumours haven't died down though and this time, they naturally move on to the iPad 3. This time, a little bit of evidence has been found that hints at the iPad 3 getting a higher resolution display.
The image above shows details of images found within iOS 5 from the built in Twitter functions. The details on the right show a higher resolution 1536x2048 display while the one on the left shows the regular resolution images.
What this means is that within the timeframe that iOS 5 runs (probably from September 2011 to September 2012), we might see the iPad 3 launched sometime in that window. Of course, we expect it will arrive sometime in March or April 2012 although we don't know for sure if the retina display will or will not be included. So far, we see hints that it will.
Images can be found over here.