Don't get me wrong I don't mind retro graphics, but I've been getting really tired of seeing every other indie game going 8bit as of late. It's like they think they're being edgy or special by going with retro graphics. Guess what? They're not! They rather play off nostalgia than make something...
With Left4Dead and Portal 2 they've been calling it Authoring Tools because there is no code. Where as Source Source-Development-Kit does have code in it to allow modders to... mod (up to Orange Box). So by saying Source-Development-Kit it makes me wonder how much stuff is going to be in it.