There are also a few forums that RPG fans like and I have seen some traffic from.
http://crowdfundingforum.com - This one is more generally targeted, but there is a strong group of RPG fans that look here for upcoming games.
http://gog.com - Has a great community.
If you are looking to do a Kickstarter Project there is a few more sites that you may want to look at I have gotten a bit of traffic from each of them.
rockpapershotgun.com - Katchup
If there are anymore sites that people can or should use you can drop them in the comments and I will add them.
Hope this helps a few people.
Edit: Added the forums to the list.