That you had no meaningful conversations last time raises some alarm bells. I have really only gone to the CoC career fair extensively once (as in went every day of the career fair my first semester at Tech), but it was a fantastic experience (now am one of the few CS students that seems to co-op with one company).

What made the experience so useful was that I was able to ask all the various companies there questions about themselves. Sure one can read online what a company does, but at a career fair, one can ask full-time workers deeper questions about the company's market, the culture of their company, what interesting work is being done, how the future looks, as well as what they see going forward for their industry. Perhaps most importantly, I was able to ask them what they think an ideal candidate looks like (so that I knew what I would need to work towards over the next semester or two to prepare for interviews if I wasn't able to get any then).

I would really encourage anyone going to the career fair to research companies that look interesting and know a bit about the company before going to the company's booth. It makes the conversation much more interesting and might lead to an invitation to an interview or make a good impression so that a follow-up email might lead to an interview later on. These people work full time at a given company hopefully because they like the product, culture, and market, or they think it is important enough to devote thousands of hours of their life to. Never before attending a GA Tech career fair was I able to have such an opportunity.

For what it's worth, I didn't get my co-op through the career fair but rather through CareerBuzz. That said, the career fair experience provided a lot of fantastic information on what some very good companies are like in my field and what I would need to do for myself to be able to achieve goals I had for myself in my field of study.