That's what I use MAL mainly for at least. I usually keep all the things I'm watching up on separate tabs but I like keeping my list updated for personal reference (gotta know just how many days of my life I've wasted on this hobby) and in case I lose all my tabs and need to know where I am in things. And knowing my completion count is nice too since I don't really keep track of things otherwise.
OMM 1: the manga site I read world trigger on is down too sighs
OMM 2: I need a haircut hmm,,,