Its just the newest version of the operating system. Most people could care less and likely wont even notice the changes. However, it does allow you to manage apparently easier and is supposed to run more efficiently, so you'd get better battery life. A few other small improvements as well.
yes...it is "supposed" to be july or august...but don't hold your breath. verizon is pretty bad with pushing updates. i just accept this, as i'm fine with how my phone is now. sure, it will be nice when the update shows up, but i don't concern myself with it, as it would drive me crazy if it gets to be september or october and we still don't have it.