It's going to be worth probably what it makes in PPC (which could be a lot as I think 888poker.com is one of the URLs 888.com uses to promote Pacific Poker (their poker site). You might get some good traffic especially from people recognizing 888 as lucky, as they might intuitively type "Lucky888" instead of just 888. If it's not getting traffic, it will be a tough sell I think, as I don't see anyone wanting to develop a whole new site trying to piggyback off of 888Poker.com.
Note: Just checked, and even though they own 888poker.com, they put nothing on that and do put Pacific Poker on 888-Poker.com. Strange...