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You are the 2000th member!
Clark lost his site when a beam of light that had went through some Krytonite hit his eyes. It was coming back towards the end though...we got to see him sport those "Clark Kent" glasses
As a result of him losing his sight, he developed super hearing. He was at school and could here Chloe and Lionel talking about him though she was on the other side of the school. He confronted Chloe about it...they had a little tiff.
He also told Lex that he heard Lionel say he was basically useless at LuthorCorp (he had heard in the Lionel/Chloe phone convo so couldn't say where he had heard it to Lex). Then Lex told Lionel he knew and Lionel thought Chloe had told Lex. He fired Chloe's dad and got her column at the DP taken away.
Clark told Lana a few things about him missing her and thought maybe cause his sight was gone (and he couldn't be "superman") the things stopping him from being with her were gone...but she pulled away and told him she met someone.
Those are the major points...It was a really great ep! Hopefully the transcript will come out soon!