Here's the versions out in the forums..
Build 6900
Build 7000
Build 7100
Build 7600

Release Candidates (RC) = 6900, 7000, 7100
Release To Manufacturing (RTM) = 7600

My thread is Build 7600. And it was released August 2009. Take note that there is no difference between August releases and the one that has been released this October.. Build 7600 is final. RTM for short.

OEM means Original Equipment Manufacturer. These versions was given ofcourse to manufacturers so that they can incorporate their software features into OS. (eg, Dell, HP, Acer etch..)

-- Is this the version released 22nd of Oct?
NO! This is the MSDN Release. RTM (Release to Manufacturing). There is no difference with the one that has been released last August and October 22 which is Build 7600.

-- Can I upgrade my current Operating System?
Vista = Yes, XP = NO

-- Are my files gonna be deleted if I install Windows 7?
If upgrade NO, If clean install YES!.. I have discussed the difference at the Installation Instructions at the bottom of this post.

-- How to install?
There are 2 types of Installation, I have explained those 2 at the end of this topic.

-- How will i know if my pc can handle Windows 7?
Before you do the upgrade and not sure if you're computer is ready to Windows 7, I suggest you to download and visit the Microsoft Windows 7 Upgrade Advisor. Scroll down to see the link i have provided.

-- Which shall I install? 64bit or 32bit?
Here's the official link of microsoft for the Windows 7 System Requiremens: http://windows.microsoft.com/systemrequirements

MD5: d0b8b407e8a3d4b75ee9c10147266b89
SHA1: 5395dc4b38f7bdb1e005ff414deedfdb16dbf610

http://www.microsoft.com/downloads/details.aspx?FamilyID=1b544e90-7659-4bd9-9e51-2497c146af15&displayLang=en

http://rapidshare.com/files/302178899/W7-86X-AKE.part01.rar
http://rapidshare.com/files/302181018/W7-86X-AKE.part02.rar
http://rapidshare.com/files/302178413/W7-86X-AKE.part03.rar
http://rapidshare.com/files/302181007/W7-86X-AKE.part04.rar
http://rapidshare.com/files/302178872/W7-86X-AKE.part05.rar
http://rapidshare.com/files/302178597/W7-86X-AKE.part06.rar
http://rapidshare.com/files/302179092/W7-86X-AKE.part07.rar
http://rapidshare.com/files/302182101/W7-86X-AKE.part08.rar
http://rapidshare.com/files/302178112/W7-86X-AKE.part09.rar
http://rapidshare.com/files/302180248/W7-86X-AKE.part10.rar
http://rapidshare.com/files/302177732/W7-86X-AKE.part11.rar
http://rapidshare.com/files/302178300/W7-86X-AKE.part12.rar
http://rapidshare.com/files/302178309/W7-86X-AKE.part13.rar
http://rapidshare.com/files/302178864/W7-86X-AKE.part14.rar
http://rapidshare.com/files/302178975/W7-86X-AKE.part15.rar
http://rapidshare.com/files/302178220/W7-86X-AKE.part16.rar
http://rapidshare.com/files/302178296/W7-86X-AKE.part17.rar
http://rapidshare.com/files/302180202/W7-86X-AKE.part18.rar
http://rapidshare.com/files/302179884/W7-86X-AKE.part19.rar
http://rapidshare.com/files/302177913/W7-86X-AKE.part20.rar
http://rapidshare.com/files/302177020/W7-86X-AKE.part21.rar
http://rapidshare.com/files/302181477/W7-86X-AKE.part22.rar
http://rapidshare.com/files/302178027/W7-86X-AKE.part23.rar
http://rapidshare.com/files/302177362/W7-86X-AKE.part24.rar

http://rapidshare.com/files/302181014/W7-64X-AKE.part01.rar
http://rapidshare.com/files/302181039/W7-64X-AKE.part02.rar
http://rapidshare.com/files/302179402/W7-64X-AKE.part03.rar
http://rapidshare.com/files/302178414/W7-64X-AKE.part04.rar
http://rapidshare.com/files/302177307/W7-64X-AKE.part05.rar
http://rapidshare.com/files/302179140/W7-64X-AKE.part06.rar
http://rapidshare.com/files/302181063/W7-64X-AKE.part07.rar
http://rapidshare.com/files/302177604/W7-64X-AKE.part08.rar
http://rapidshare.com/files/302179740/W7-64X-AKE.part09.rar
http://rapidshare.com/files/302179883/W7-64X-AKE.part10.rar
http://rapidshare.com/files/302176870/W7-64X-AKE.part11.rar
http://rapidshare.com/files/302179770/W7-64X-AKE.part12.rar
http://rapidshare.com/files/302180700/W7-64X-AKE.part13.rar
http://rapidshare.com/files/302180207/W7-64X-AKE.part14.rar
http://rapidshare.com/files/302181133/W7-64X-AKE.part15.rar
http://rapidshare.com/files/302178853/W7-64X-AKE.part16.rar
http://rapidshare.com/files/302177002/W7-64X-AKE.part17.rar
http://rapidshare.com/files/302181398/W7-64X-AKE.part18.rar
http://rapidshare.com/files/302180790/W7-64X-AKE.part19.rar
http://rapidshare.com/files/302180144/W7-64X-AKE.part20.rar
http://rapidshare.com/files/302181379/W7-64X-AKE.part21.rar
http://rapidshare.com/files/302181028/W7-64X-AKE.part22.rar
http://rapidshare.com/files/302177044/W7-64X-AKE.part23.rar
http://rapidshare.com/files/302181402/W7-64X-AKE.part24.rar
http://rapidshare.com/files/302179892/W7-64X-AKE.part25.rar
http://rapidshare.com/files/302179373/W7-64X-AKE.part26.rar
http://rapidshare.com/files/302181037/W7-64X-AKE.part27.rar
http://rapidshare.com/files/302178482/W7-64X-AKE.part28.rar
http://rapidshare.com/files/302180565/W7-64X-AKE.part29.rar
http://rapidshare.com/files/302177821/W7-64X-AKE.part30.rar
http://rapidshare.com/files/302176896/W7-64X-AKE.part31.rar

http://hotfile.com/dl/15511222/0102921/AK7-AKE.rar.html

-- Download and extract the ISO file:
-- Burn it using your favorite burning software:
-- Install and follow the Installation Instructions:
-- Extract the Activator. I included 3 of them, The first one includes the screenshots on how to activate:

-- There are 2 types of installation, Clean install and Upgrade.. Upgrade means you will keep all the files inside your hard drive. Take note that Upgrade is only available if you are using Windows Vista. If you're using WinXP, forget it. The next one is the Clean installation.. This is the easiest and the fastest. It will reformat your drive and install the Windows 7 in a fresh hard drive. It will take only 20-30 mins.

-- Take note that you also have 2 options to install. Via DVD or USB. The first instructions above is via DVD but you can also intall it using USB.. to do that, use the Google and there are a lots of articles and blogs that teach how to make the USB bootable. Google is everyones partner, sometimes don't just ask, be resourceful..