Clark: Lois Lane? This is the red-blue blur.
Lois: Yeah, right. How do I know you're not some
deep throat wannabe (informer?)with a lot of time on his hands?
Clark: Look down. (Here she sees the letter she sent him)
Lois: Okay. Call me Lois if you want to. And while we're at it
do you wanna weigh in (Give your vote?) on the whole 'red-blue blur' thing?
Because it's kind of a mouthful on this end. Hard to pronounce it when ending on 'blur'?[:^)]
"Deep Throat" is the name that was given to an important informer during the Nixon Watergate investigations. The person eventually revealed his identity and then died just a few months ago.

Weigh in = explain

Well, it is difficult to pronounce, but I think it's more likely to mean 'confusion'.
Thanks, Philip!