It's a double-edged sword is it not? We want better quality, we want higher MP sensors (well not everyone), and we want it for the same price as we paid for the previous iteration...
As per CR guys recent posts, Canon like Nikon are upgrading all their lenses to match the next iteration of high quality sensors. Does the price (fairly) reflect the cost of developing higher quality lenses or are they making some creative leaps in pricing to make up for any loses on bodies?
The 100-400mm was my first L lens, and boy did I get a duff copy. If I could get a reliable replacement, with increased quality, and it would do me for the next 2-3 generations of dSLR bodies then I would be happy, but everyone has different requirements.
It will be interesting to see if Canon intentionally nobble the successor in the same way they have for the 70-300mm f/4-5.6L IS so it can't take a 1.4x converter to protect it from impacting on the 200-400mm. I suspect they will, which is a shame....
**updated to replace the typos on lenses