You're both right. But remember that high margin products are not money makers without volume. Canon makes more money in consumer imaging selling rebels than it does any other slr. A dual announcement with real differentiation between the technologies obviates the problems you both describe. The problem Canon has created and the world of Canon shooters has had to live with during these past 4 years or so is there is either too much or not enough product differentiation between technologies. Think of it this way:
1) there is NO one Canon camera that does everything (1Ds3 and 5D2 have their own strengths and weaknesses, price, sensor, AF, ruggedness, etc)
2) important technologies work their way into lower level models whose core specs don't meet the photographer's needs (7D has a wonderful AF system and is more rugged than a 5D2 and a hell of a lot faster, but does not match IQ of the full frame 5D2 OR 1D4 meets the ruggedness and speed and focal length multiplier criteria for sports shooters, but lacks the detail in files that the 1Ds has).
What do people who frequent boards expect and or want from these cameras? Hopefully Canon will exceed our expectations but those expectations go something like this:
-full frame sensor upgrade
-low light capability
-modest frames per second bump (maybe 4.0 or 4.2)
-improved auto focus (everyone cites the 7D as a target)
-improved ruggedness and weather sealing (this is after all a tool used widely by landscapers and outdoor shooters)
-major full frame sensor upgrade (very high resolution (push into medium territory which means 40+ MP minimum for studio work)
-low light advantages over medium format (so clean ISO 3200)
-frame per second advantages over medium format (think minimum of 5 fps)
-built in triggering and command for strobes
-rugged with ample battery life
So, if Canon wants to make a FF splash with a significant upgrade, it will be the 1Ds with a lesser version in the form of a 5DM3 to follow many months or even year later. Canon wouldn't want those who have been waiting for new FF to have all bought the 5DM3 when they announce a new 1Ds.
Nor, after a 1Ds4 introduction, do they want prospective 1Ds4 buyers to wait for a 5DMk3 that they expect to come, especially if those buyers already own a 1Ds3 or 5D2 and find their current cameras' image quality to be acceptable for most or all of their work. This problem isn't unique to Canon. There are a considerable number of Nikonians who have been impatiently waiting for a D700X with the D3X sensor and a D700S with the D3S sensor.