The OpenERP Community Backports are a set of branches that add additional bugfixes to the official OpenERP branches. It consists of the following projects:

https://launchpad.net/ocb-server
https://launchpad.net/ocb-addons
https://launchpad.net/ocb-web

Currently, series 6.1 and 7.0 are supported.

The branches are updated nightly with missing revisions from the official branches.

Please read the thread with the original proposal: https://lists.launchpad.net/openerp-community/msg02197.html

You can also read about the history of the 6.1 branches here: https://answers.launchpad.net/ocb-addons/+faq/2254
The 6.1 branch contains functional changes listed here: https://answers.launchpad.net/ocb-addons/+faq/2255

Functional changes are not encouraged, especially if they change the database layout. In any case, if a change to the database layout should get approved, it should have an additional commit tag '[UPG]' on the first line of the commit message. For example:

    [FIX] [UPG] lp:707923, account: Effective vertical tax rounding by increasing precision