Dmoz never indexed sites, never has or will - it's not a search engine - it's a human edited directory which you have to submit to for inclusion. It's extremely difficult to get in but it isn't essential to have a listing there to achieve good rankings.
However, a DMOZ listing will help your search engine rankings. Google is known to apply a higher weighting score to links given from Dmoz because it can indicate the usefulness of the site to the web as a whole (in theory).
Personally I think the quality of the site's listed on Dmoz are questionable. There's a mix of okay and terrible.
It was much easier to get in 8, 9, 10 years ago when it was young than it is now, so if you managed to get your mediocre site listed in 1999 and you haven't let the domain expire you're laughing.
There are site's on there that offer no value whatsoever, they've just been there since the beginning so they'll stay there. They're part of the decor.
If you've got a recognized brand, you're more likely to get in. If not then you're at the mercy of the Dmoz editor for your websites category.
There were some site's that I have been trying to get in for years with no luck, other's I got in on the first or second attempt (not many though). I've actually given up with Dmoz, I tell people how to submit for best chance of inclusion - it's up to them if they want to persist.
There is a backdoor that I haven't tried for a couple of years - have a look through your preferred category for expiring domains. There are a lot of domains that were registered in 1996 - 1998 for the maximum period of 10 years that will now just be expiring. If you can snap them up, you've got yourself a Dmoz listed domain to build on or 301 redirect to your main site. There are usually multiple categories that your site could fit in to so there's usually a few worth watching.
