It's surprising to learn that, before "Big Bang" producers found Jim Parsons and cast him as Sheldon, Lorre talked to Galecki about playing that character. Galecki said he didn't "get" Sheldon, however, until he saw Parsons play the role.

But Galecki added that he's very pleased to be playing Leonard, especially given that his character and Penny begun a romantic relationship, which has played out in a low-key, realistic way this season.

"I rarely get to play those characters and explore relationship things. I usually play the character's best friend or assistant. Or gay assistant," Galecki said.

Though Sheldon has become "Big Bang's" breakout character, thanks to not only the show's solid writing but Parson's detailed, deadpan perfomance, one of the quieter pleasures is Galecki's steady, subtle work as Leonard.

"I don't know if I would characterize Johnny as the 'straight man,' but his character is certainly much more willing than Sheldon to try to conform to social expectations,'" co-creator and executive producer Bill Prady said. "I think the fact that, despite everything, Leonard considers Sheldon his best friend reminds us of Sheldon's essential humanity."

Actually, Galecki was fine with it when I used the words "straight man" in describing his role.

"There's a very specific responsibility in it," he said. "It's like in hockey -- you get a lot of credit for assists.

http://featuresblogs.chicagotribune.com/entertainment_tv/2010/01/big-bang-theory-johnny-galecki-cbs-sheldon-leonard.html

Hey I'd be thrilled to be the straight man too if it meant i got to play Kaley's boyfriend! I think Johnny Galecki is great on the show and should have been nominated for a supporting actor Emmy.

Great cast, cool show. My current obsession !

I think the entire cast is a good one.