Gotta love rivalry. Jamba Juice is upping the ante in its battle against McDonald's to win smoothie lovers by accepting all McDonald's smoothie coupons through Aug. 15, 2010. Jamba Juice is even accepting McDonald's coupons for FREE smoothies. You will recall that McDonald's abruptly canceled its free smoothie promo last month.

The deal is only happening in select cities, however, so if you do not live in Los Angeles, San Diego, New York City, San Francisco, Sacramento, Miami, Chicago, or Denver, you're out of luck. But no matter where you live you can print this Jamba Juice coupon to get $1 off your next smoothie. Expires Sept. 1, 2010.

Jamba Juice even made a commercial poking fun at McDonald's launching a smoothie line, something they say makes as much sense as making a "Cheeseburger Chill" smoothie. Gross!