hi can i know.Unity4 free version release date?=free version for educational purpose
Unity 4 has no release date, as such the free version that will not be released until then either does not have one either.
Or put into the words used by staff members ‘when its done’ 
Can’t comment on the educational licensing, thats a thing you will likely need to clarify with the place you get it from.
Unity free is fully commercially usable though you can only legally use it if your / the using legal entities yearly gross revenue is < $100k USD
The places selling the Edu 4.0 license are very misleading, I got mine from Studica.
Edu licenses don’t get the beta, they advertize a 4.0 license with the all the bells and whistles that come with it and then they give you a 3.5 license, don’t give any indication of when you’ll get 4.0 or if you will even get it before the (4.0) license you bought expires. Maybe its clarified somewhere and I missed it but I wouldn’t have even bothered with it if I knew this was how it was delivered =/
Just FYI from my experience with the edu.