At my company we tend to use "NOTE:" just to be aware of something, "XXX:" when something's functional, but has room for improvement, "TODO:" when functionality

At my company we tend to use "NOTE:" just to be aware of something, "XXX:" when something's functional, but has room for improvement, "TODO:" when functionality's missing, and "FIXME:" when it's plain broken. In that context the XXX's are kinda nice to have... we can mark there's something to work on; but only search for TODO/FIXME when looking for things that will actually impact currently needed operations.