Having your game listed in online directories is a good way to promote your game and also get some few links.
So, in this thread, I'll some some directories that are for online games:
@Hituro @Tyler @Zarabeythe @PaulSonny @Ardy @vplspride @Claws
Those are some that will drive pretty good traffic to your game. These sites helped a lot of games grow in the past, and I don't see any problem with getting your online game listed on them. And plus, more links are always good. So, if you know of any other online games directories, please list them here.