There are certainly similarities to Renaissance Florence in the concentration of talent in a small space and the air of competition -- but if you're talking about quality of mind, it's unlikely we'll ever see three people like Leonardo da Vinci, Raphael, and Michelangelo working at the same place and same time ever again ...

That's possible, but I don't think you can tell right now. We have had hundreds of years to realize just what those 3 geniuses accomplished and marvel at the fact that they were there together.

Look at today's PayPal mafia for example. If Peter Thiel, Max Levchin, and Elon Musk accomplish in the next 30-40 years what they have stated as their goals, the significance for the human race could easily parallel what was achieved in the Renaissance.