Hi Darren,
I think you have fairly much summed it up for the compact side of things. Canon have been going that way for a while - the G10 was 14.7MP, while the G11 and G12 are both 10 MP.
Interestingly, I see that Canon have backed-off on the No. of pixels in their pro full frame sensor. The new full frame
18MP 1DX will replace both the H-sized 16MP 1D mkIV and the full frame
21MP 1D mkIII. They have maybe decided that 21MP is enough for anyone stopping at 35 mm equivalent photography - and they are probably correct. I have a C-sized 7D with 18 MP crammed onto it. I've had some of my photos printed at 30 x 20 inches. The resolution at 173 ppi is fine - you stand back a bit to look at a 30 x 20 anyway
They are obviously taking the chance to save having to upkeep 2 pro lines, and by backing off a bit on the 1Ds pixel count they can keep the speed up with their new processors. The 1DX will have up to 14 fps burst mode - that's a whole lot of curtain movement! They will maybe keep the 5D line going with the high pixel count for those who don't need the high burst speed. I quite fancy a move up to a 5D, but I like the 8 fps I get with the 7D and wouldn't go to a 5D unless the next marque is a fair bit faster.
Col