Need quick advice with 2010 Bianchi Via Nirone 7 Alu Sora 9sp mix Compact

[grandamn]

I have have the opportunity to buy a 2010 off of my cousin for $650. Is it worth it? Will it make a significant difference from my Kent GMC Denali?

http://www.bianchiusa.com/archives/2010/coast-to-coast/via-nirone-7-sora-compact/

How much is this thing going to weigh with a 57cm frame?

I saw it say the rear was a 9 spd does that mean its really 18?