According to NASA, the global average surface temperature in 2011 was the ninth warmest since 1880 and 9 of the 10 warmest years in the modern meteorological record have occurred since the year 2000. To illustrate this trend NASA has produced an animation that illustrates temperature data from 1880-2011. Red indicates temperatures higher than the average during the baseline period of 1951-1980 while blue indicates lower temperatures than the baseline average.
The Berkeley Earth Surface Temperature study produced a similar animation and Novim, the nonprofit group that sponsored the study, has now produced an iOS app where you can play around with it. This animation goes from 1800 to 2009, again compared to local averages between 1950 and 1980.