Open Stack

> i plan and want to deploy some production vm server on openstack cloud
> architecture, but since openstack have recently update to havana ,
> what version that suited to used on production? i plan to used havana
> with all latest technology like neutron, heat and quantum.
> and if it released new version, am i must follow this progress?

I really would certainly start with Havana.
If you do not you will have to do the quantum => neutron rename at a later time which is a pain.

We are running production on Havana on SL6. (Started with Folsom, upgraded to Grizzly and now to Havana)
With the current pace of development I think it is probably a good thing to keep close to the new releases.
Every release had stuff that we wanted anyway. Maybe in a few years things will look different when things have settled more.
Also, upgrades for us so far have been, relatively, painless. 
(Just had a few small bumps with the db upgrades. Make sure you have a mysqldump before doing those. :)

Cheers,
Robert van Leeuwen