In the chromium blog it's mentioned that webpage-instantiated NPAPI plugins are not supported anymore starting in january. (http://blog.chromium.org/2013/09/saying-goodbye-to-our-old-friend-npapi.html)
Otherwise http://www.chromium.org/developers/npapi-deprecation says that:
Apps and Extensions that use NPAPI plug-ins will not be affected by the initial January 2014 block.
Our extension uses a npapi plugin in the backgroundpage and also inserts one into the contentpages. Has anyone further informations about how the january changes will affect the extension?
The linked pages don't say anything about stopping plugin support in january - they say most plugins will be blocked (i.e. made click-to-play).
The Chromium article says:
Apps and Extensions that use NPAPI plug-ins will not be affected by the initial January 2014 block.
[...]
If your NPAPI plug-in is installed by a wrapper extension and then used by pages on the open web, it will not be affected by the initial January 2014 block. It will follow the Apps/Extension deprecation path instead.