Turns out, the two superstars are not just costars, but good pals, as well.
"George and I have known each other for over 20 years. We've known each other since we got out of college and we have the same group of friends," the Oscar-winning actress, 49, told reporters at Monday's Gravity press conference at the Toronto International Film Festival.
"We knew each other since we had no work," she quips.
Despite their subsequent fame and success, Bullock says Clooney, 52, has remained the same person except for one thing.
"He has better hair now!" she kids. "There's less of it, which I appreciate. The big curls were cute, but you know … Really, he's taken his blessed life and done amazing things with it."
Bullock may adore The Monuments Men star, but the biggest Clooney fan is her 3½-year-old son, Louis.
"My son thinks he's a very cool dude. If there was a choice between me and George and [director] Alfonso [Curaón], my son will leave to go with George and the guys," she says. "He's a boys' boy – he has to go and talk to the men."
Recently, little Louis even requested to have some male-bonding time.
"He asked, 'Where's George and Rande [Gerber]?' I'm like, 'What? I don't know.' He goes, 'I need them.' We went to meet with them and they had man time. I stood off to the side and waited for them to finish," she says with a laugh, "and then I was allowed to take him back."
The proud mom appreciates Clooney's willingness to spend time with her son.
"George is a good man, and I'm really proud to have known him for this time and the human being he's become,” she said. "He's a good egg."