On the DVD is a very short commentary by Craig McCracken about the show in general. My forum Graphics Coordinator CG transcribed it for me...enjoy!
Craig: Foster's is basically really bizarre surreal characters living in this house together and just the daily life things that they have to deal with.
[Scene from House of Bloos]
Bloo: Do you have any idea what I’ve been through all day?
Craig: I’m really a little bit surprised by how quickly people really gravitated towards the show and started just enjoying it, the characters and getting the humor and really getting the idea of it. It felt really good to have it like, uh, become pretty popular and getting a good response for it really quickly.
[Scene from Partying is Such Sweet Soiree]
Herriman: [on the phone] Hello, Foster's Home For Imaginary Friends?
Craig: It’s cool that like, different audiences have found different characters that they can gravitate towards. Little little kids really love Eduardo just because he’s so sweet, and big and loveable.
Eduardo: I am, how you say, tightly wound emotionally.
Craig: Older kids really like Bloo, just because he’s so funny and we found out there’s these huge factions of teenage girls who have, really have, like crushes on Wilt because he’s such a nice guy.
[Scene from House of Bloos]
Wilt: Hey how you goin’?
Craig: And also I noticed a lot of parents have enjoyed watching the show, y’know. I’ve had people tell me like, it’s so refreshing to see the show. It’s just about relationships and friendships and people hanging out together.
[Scene from Partying is Such Sweet Soiree]
Wilt: Have you lost your marbles?
Eduardo: I no have no marbles!
Craig: When I first started off the show I was kinda getting a lot of flak for, you know being a little bit weird, a little bit off cuz I had all these imaginary friends. But since the success of the show, everyone has been really cool about it, everyone has kind of come out of the closet and been a lot more open about their imaginary friends.
[Shot of Andy, Digital Artist sat next to "Lt. Lupie," his Imaginary Friend (we see nothing)]
Andy: We been together about six, seven months now. [turns to chair, listens for a moment] Eight months? Really? That long? [back to camera] Wow, eight months now.
[Scene from House of Bloos]
Bloo: This place is crazy!
[Shot of Jeff, Production Assistant]
Jeff: People might laugh, and they might point, they might judge. But we know what’s real, and it’s in here. [thumps chest]
[Shot of Jeff walking down a hallway with "Tickles," his imaginary friend (we see nothing)]
Jeff: I said the exact same thing to him, I know right to him. [another guy walks up, walking right through where Tickles was "walking" causing Jeff to stop walking and look after the man] Dude. Hey. Walking here.
[Scene from House of Bloos]
Wilt: And speaking of friends,
Craig: [voice over while a few shots play] They totally understand you more than anybody else. They can get you stuff, you know you thought of 'em so they kinda owe you everything.
[Shot of Adam, a Writer having lunch with "Dyno Mite," his imaginary friend (again, we see nothing).]
Adam: [laughing] To you! No, you’re right. To us. [raises glass in cheers]
[Shot from House of Bloos]
Wilt: You sure have a way with words!
Craig: [voice over on another man, in the men’s toilets with his (unseen) imaginary friend] It’s actually, it’s made it kinda cool to have an imaginary friend. There’s nothing to be, you know, ashamed of anymore.
[Shot of some of the artists who work on the show shouting and hollering through a plate glass doorway. Inside the room a hulking man is fighting with an (unseen) imaginary friend, and losing horribly. It then shows a lady massaging her (unseen) imaginary friend's shoulders. Another man, petting and kissing an (unseen) imaginary friend that’s small enough to sit in his hand. More imagery of the man fighting the imaginary friend, still losing. Another man answers the phone, then passes it onto his (unseen) imaginary friend claiming it’s for him.]
Craig: I hope we can just continue to make a really good, exciting, funny show that people enjoy watching. And I would love it to be the success that Powerpuff did.