Always, although I never use TODO for fixes or for hacks (never even used the HACKED task), in fact all I use TODO for is for future additions to the project that I want but don't have time to implement yet. For fixes / hack checking isn't that best done through unit tests and have full code coverage of the area, at least that way it would always fail until you fix it and you can apply the assertion checks globally too if necessary as a fix in one area could just give birth to a bug in another.
Edit: Ofc this isn't always the easiest way to test graphics / sound / scene logic issues but then sticking a TODO flag may not be the most efficient method either, well not for me at least anyway