I hope this is a new trend for Canon.. it certainly seems that way.. but after REALLY updating the Canon 7D with the latest firmware, Canon has announced they will be upgrading the Canon 5D Mark III firmware. The notable updates will include uncompressed HDMI output and an improvement to the auto focus system. The AF improvement will allow the Canon 5D Mark III to adjust its AF algorithms to the type of lens used on the body.
Its great that Canon has been adding new features to their existing bodies. Hopefully they keep it up.