thats from a blog, refer to microsoft technet for more uptodate version info:
September 9, 2014 update for SharePoint Server 2013 (KB2889864)
This article describes update KB2889864 for Microsoft SharePoint
Server 2013 that was released on September 9, 2014.
This update includes stability and performance improvements.
http://support.microsoft.com/kb/2889864
this build version is updating on the 12-Aug-2014 update that contains those files and carried on from 27-Jul-2014 update.
http://support.microsoft.com/kb/2760319
so that being said you can refer to this:
it shows you the latest builds for each area
http://technet.microsoft.com/library/dn789211%28v=office.14%29
latest build is:
This is build 15.0.4649.1001 of the cumulative update package
check manual way for verification on updates applied onto server:
central admin -> upgrade and migration -> check product and patch installation status
EDIT
ok i understand your frustration but if your updating correctly and that sharepoint is uptodate than there is no reason to be conserne. as i noted it could be several issues that could cause you to get the different build number:
to understand what is going on look into the powershell code your using:
(get-spfarm).buildversion
looking on msdn it states the following for the function SPFarm.BuildVersion
:
Gets the Microsoft SharePoint Foundation build version of the server
farm.
now read this as noted earlier:
As a result of the packaging, it is no longer necessary to install the
SharePoint Foundation cumulative update and then install the
SharePoint Server cumulative update.
also like to note:
the powershell is looking up on build version not patch build version!
if you were to look into the kb for october you would see some items on old build and some on new builds. But the overall build from powershell is correct.
EDIT
Yes its important that you run wizard every time you do a CU,
I would:
1) install CU
2) reset server
3) run SharePoint Products Configuration Wizard
4) reset server
5) check to make sure by running powershell code!
the SharePoint Products Configuration Wizard will update the content database and configuration database with the update and apply any patches.
its very important to apply cu on all front end servers before you run SharePoint Products Configuration Wizard!!!!
Run the SharePoint Products Configuration Wizard on the Central
Administration server (APP-1) to upgrade the configuration database
and upgrade each content database serially.
also note:
Run the configuration wizard to ensure that if an update fails for a
specific server, the error is not propagated to the other web servers.
For example, a failed update for one server could make the update fail
for one or more site collections.
for a full setp guid from msdn on adding CU and updating with SharePoint Products Configuration Wizard then refer to this:
http://technet.microsoft.com/en-us/library/ff806338%28v=office.15%29.aspx