I looked back to try and find some of the older threads where we've discussed this but in short, Project is a legacy term from the very early days of the Agile Central (formerly Rally) product that's pretty deeply baked in. We're all in agreement that it needs to be changed and the CA product team is looking into it, so there's light at the end of the tunnel.
From my experiences both as a customer and now as a CA employee it's inconvenient but very achievable to get your users accustomed to Project = Team, just takes a while to socialize the knowledge. "Release" is a similarly loaded term in AC so you'll want to pay attention to that as well, and rest assured that the CA product owners and managers are working on it. Hope that helps.