There is a dangerous Catch-22 in D7 for multlingual sites. You can easily and silently lose your tagging and node references depending on what lang you are in when you edit a node. JA=Japanese, and EN=English.
The Catch-22:
1. Start in EN interface. 2. Add Content > News. 3. Fill in info, setting lang=EN and assigning node and term references. Only EN and neutral items are available, which is expected. 4. Save. 5. The user is sent to node view of http://www.mydomain.com/press-room/news/2012/4/20/title 6. Click Translate.
The translation begins with copies of the English content, including the Term and Node references, but the nodes are to English. You cannot select the JA nodes to reference because you are in EN interface. You must manually alter the URL to switch to JA interface and then manually delete text like "[nid:3579]" that appears in the node reference fields before replacing them with their JA counterparts.
If you have Term Reference fields that pull from Translated taxonomy Terms, it is even more dangerous, because if you open a Japanese node or editing when using the English interface of the site, the Terms are silently deleted from the Term Reference fields. If you save, you will delete all your tags without ever having received a single warning.
In other words, the node and term reference fields in the Edit screen are filtered according to the language of the user interface, not the language of the node being edited. The result is that editing a node of Language=A from the user interface language=B wipes out Language=A node and term references.
Suggestions:
A. The system should either switch the user interface to the language of the content when editing a node OR filter the node and term reference choices by the lang of the node, not the user interface.
B. Also, it would be convenient if, when the system creates the translation node and copies over the source language content, it pulls in the paired translation items of the referenced nodes and terms and puts them into the new translation node instead of the other-language originals. However, this is clearly a "nice-to-have" and would probably cause problems of its own when there is no translation of a node or term, etc., so B should be left to the future.