Great stuff. I've been to Belem once and Manaus twice - my wife is from Sao Paulo. I love Brazil and most Brazilians are wonderful people. Great, great job on your trip.
My dream has always been to kayak from Manaus to Belem. We did a short trip this summer on a combination
riverboat/kayak trip. Maybe I'll find time to cycle it also.
If anyone wants to spend any significant time in the jungle itself, let me know. I can recommend a guide in Manaus who will be happy to show you the ropes. Otherwise, there's enough in the jungle to make you regret going in untrained.
Again, congrats on an outstanding trip.