I'm working on a Milestones system for the website at the moment. Right now, it'll be set up for milestones based on join date, post count, cash amount (yes, I'm also adding cash to the website!), and account details (for example, when we add fields for AIM and profile descriptions, there could be milestones for adding that info to your profile). Each milestone will have a certain cash reward, and a future possibility might be special user titles.
On that note, I have an idea for the experience/level system, and it's based a good bit on WoW (gee, go figure). So, we have a certain number of levels on launch (we can have level icons, but we don't necessarily need them). To earn experience points, you complete "daily quests" (vote on a certain number of items in the portal, make a certain number of posts, etc.), then when you complete the quests you get cash and experience. When users hit the level cap, the experience they would earn is converted to cash. We can arbitrarily raise the level cap from time to time, there can be level-based milestones, and we could even do a "rested experience" type of system to keep casual users coming back (they may not want to visit the site on a daily basis, but if they have a reason to come back on a weekly basis because of the rested experience, that might improve our return rates).
For new users, we could have regular-type quests to make their first posts, first portal submissions, etc. We can also have seasonal quests to generate user interest from time to time.
Yes, this all sounds a lot like WoW, but I don't see any reason why it wouldn't work on RG. It would put some distance between us and NG, without looking like we blatantly ripped off another website's system. Thoughts?