For what it's worth, and based on no inside knowledge whatsover, just my experience in sales, my money is on two DSLRs being announced next week. First up, the 650D. The 25th anniversary of the EOS 650 launch is just too good a marketing opportunity to pass up. Then we get into more interesting territory. At a guess, I'd say the 5DX will be announced next week, probably at 22MP. And then in time for Photokina in the Autumn (or fall if you prefer) a 3DX at 45MP. Or just possibly vice versa.
My concern though is not much leakage yet, which seems odd.
The waiting is driving me nuts ... just like the rest of you.
If the 650D is a reheated 600D I'd say it would certainly make sense to launch it at the same time as the new 5D, get a bit of reflected glory and bypass any criticism.
My guess with the high megapixel body is that Canon has been working on something but hasnt desided whether to release it yet. If reaction to the D800 isnt favourable(E.G. if even Nikons best lenses don't live up to the sensor) and a 22MP all rounder 5D is selling better they may do without it.
I do have a sneaking feeling that Canon is going to look to have something a bit mroe eye catching to annouce beyond the specs we've seen which seems like more of a perfection of existing standards than anything radically new, 4K video? very low price point?