Yes, MacBooks and iMacs outsell their other computers, but if you look at Apple's 2Q11 earnings, Macs only account for 15% of their revenue - iPhones account for over 75%.
I did not know that. Does that mean that iPods now account for less than 10% of revenues? Wow! I knew the market was changing, but didn't realize it was changing that fast.
The pooint of all that is that the 'professional following' is really not important to Apple's bottom line, and it never has been. The same is true for Canon - revenue from Rebels and sub-$250 consumer lenses is far greater than that from 1-series bodies.
Comparing apples to oranges here. Nobody buys an iPhone because of Apple computers. But, there are plenty of people who buy Canon cameras because Canon has positioned itself well in the professional market.
The latter, like the supertele line, are developed and produced for a niche market, which is really mostly about prestige and brand recognition.
Okay, that's more accurate. Although it's more than just prestige and brand recognition. It's also about spreading R&D costs over the maximum product lines. And, it's about moving customers up the product line. This is much different than a company like Apple. I own an iPhone, but there is absolutely nothing about that phone that is going to make me want an Apple computer. On the other hand, Canon knows very well that a certain percentage of Rebel users will progress up their line. In fact, I'd love to see the statistics on the number of 1Ds owners whose first SLRs were Canon. I'd wager it's a high percentage.
Now, getting back on topic. If there is a divergence between video and still models of the 5D (or any other line), I believe it will be for design and engineering reasons, not marketing. It may be that Canon feels it cannot simultaneously optimize performance for both stills and video in the same camera. If that's the case, they may be forced to offer one version optimized for stills (with video capability) and one version optimized for video (with still capability). I think they would be loathe to do that, but design limitations could force that to happen.
Right now, the 5D has two major professional customer bases that Canon wants to protect: wedding and portrait studio photographers and independent and commercial film producers. If they feel they can satisfy both groups with one camera, they'll do it. If they find that the demands conflict, they may be forced to diverge the line.