At JILT we rely on various tools for QA depending on the nature of the localized content:
For MS Word document based translation projects, we rely on a set of macros that ensure no missing title, underlined text, bulleted item, hypertext...etc.
For website localization projects, we rely on standard HTMQA tool which validates the localized version against the source, generating logs for missing tags, titles or formatting elements.
For software localization projects we depend on Alchemny Catalyst Validation utility. Through this power feature of Catalyst we can validate target version of the software for truncated texts, hot key conflicts...etc.
For DTP projects, we do QA visually, comparing the source against the target for detection of any formatting or style mismatches. We also make sure that everything has gone left to right including images, titles, text box, illustrations, page numbers...etc