Canon has announced it has successfully developed an APS-H-size CMOS
sensor that delivers an image resolution of approximately 120 megapixels
(13,280x9184 pixels) the world’s highest level of resolution for its size.
http://cpn.canon-europe.com/content/news/120_megapixel_apsh_format_cmos_sensor.do
When the 18Mp sensor of the 600D produces files that are 20+ Mb in size and the 21Mp sensor of the Canon 5D Mark 2 produces files of nearly 30Mb just imagine the storage and processing power that your computer will need to edit the files from a 120 megapixel sensor.
I guess it won't be coming soon but shows what can be done. When the first Canon D30 DSLR was released with 3Mp sensor and the top of the range now has 21Mp (7x the size)around 10 years later, it is entirely possible that we will see 120Mp sensors in the not too distant future as it is "only" 6x the current sensor resolution.
