Oh, see, I didnt want to turn this into an argument.
Online Gambling is ILLEGAL, if it wasnt, I would be advertising my website on the newspapaer, tv; many online casinos will be established in the US, not in the island somewhere, etc. That’s why the government took the money from discovery.com for “the advertisement”, that’s why google and yahoo do not support ads for gambling websites (but yahoo.co.uk does)…
I am talking about the USA, of course. An example of legal online gambling is U.K. – it’s legal there 100% – everytime I watch a soccer game I see bilboards for 888.com
My point – you are waisting your time attempting to sue somebody over online gambling matters…The chances to find a hungry lawyer, who wasnt good enough for the “big money” is pretty good, but finding a judge to plead infront would be a husstle. The only thing you could do is “scare” the other person, but having the lawer call them, or send them a letter or something…but that’s about it.
And again, you can register any domain you like. If you didnt want something like that to happen – you should have register list-o-bonuses.com yourself.
Personally – I would have NO use from registering domain like that – the search engines make a very good destinction between the domain names, and I doubt that you have “type-in” traffic – I have never heard of list-o-bonus.com and I sleep on my keyboard, and second, there is no way of misstyping bonus to bonuses…
I see this as a “fair” game, survival of the fittest, if you like. Now, spam, that’s a serious issue.
P.S. Just to clarify – I am not the one who registered list-o-bonuses.com 
P.P.S. For Dominiqe and other interested readers, here is a link to an article:
http://www.newsmax.com/archives/articles/2004/12/16/232522.shtml