I too have heard the rumours...Canon should announce stuff next week - it's our local annual PPA school and canon ALWAYS announces stuff on the Tuesday of the school week - cause I'm there and won't know about it till the weekend.
This year I'm not going there, but will be in Detroit Wed/Thurs, so I'd expect their announcement to be then
so again, I'll be 2 days behind the rest of the world.
I've heard 16mp FF (new sensor) and new AF system with 21 points, and ISO 12,800 with a push to 25,600, weather sealing ala the 40D. $3499 But that rumour says availability June 2.
I've also heard a rumour of a second 5D that is a 12 mp 1.3 sensor...and priced around $1800...a Nikon fighter, slot filler type thing.
No matter the rumours, I'll believe it when I see it. And if it has a new AF system I'll buy it.