Office 2013 should install the appropriate IFilter to handle those file types.
We installed the 32-bit version of Microsoft Office Professional Plus 2013 on Windows 8 Pro x64 and IFilters were installed for both 32-bit AND 64-bit applications. The IFilters covered all the usual office formats (e.g. doc, docx, xls, xlsx) but also for ODF formats, such as odt and ods.
The IFilters were tested using 64-bit FileLocator Pro and included tests on normal DOCX files and also DOCX files saved in *Strict Open XML Document (.docx)** format.