Many manufacturers have introduced rebates programs. Usually new products are not introduced when there is an ongoing rebate campaign, which also means slow times for the rumor mill. Also, all major players are preparing for Photokina (coming up in September, 2010) and don't want to show their cards in advance.
Here are the latest rebates:
Canon 50D: $100 rebate
Canon 50D + 28-135mm: $100 rebate
Canon 50D + 28-135mm and 70-300mm: $250 rebate
Canon EOS 50D SLR Digital Camera Kit with 17-85mm Lens: $400-$500 conditional rebate
Canon EOS 50D SLR Digital Camera Kit with Canon 18-200mm EF-S IS Lens: $400-$500 conditional rebate
Olympus E620: $50 rebate
Olympus E-30: $100 rebate
Olympus E-3: $100 rebate