We have just returned from a two week tour on which our hotels, breakfast and transport were already paid.
We spent a total of $520 for 2 people. This covered all our lunches, dinners, drinks and souvenirs. We didn't try and economise either. The souvenirs included 2 men's traditional shirts, a silk/cotton blouse, a longyi, a hand made silver bracelet, a bamboo hat, a handmade paper parasol, 3 bags, 2 handwoven scarves, 2 T shirts, a lacquerware tray, lacquerware box and lacquerware drinks mats plus box!
So your money will go a long way. Also recommend buying things up country when you see them - better choice and quality than in Yangon we thought.
We changed all our money into kyats and did not need dollars, but some places you could use either, so useful to have dollars as back up.
Edited: 13 February 2012, 23:50