Nothing wrong with Opera, especially with the emergence of the mobile market. That said, it's a good desktop browser, too.
The site looks interesting, I'm kind of withholding judgement to see how things break down. A site like this has a few concerns:
1) Do the creators/maintainers play any of the listed games? While playing the games is essential to know what kind of features need to be implemented, there has to be a lot of trust from the users if this is the case. IE. "I didn't get the TOD for KB... oh, let me just scan the "X server" database." Please know this isn't accusatory, but it's something you (and users) should think about.
2) What are you planning to make the "premium" features? Have you decided yet?
3) Since you're essentially a stated for-profit company (right?), you should probably get your legal stuff up there asap, especially now that people are making accounts and such, even if it is beta.
You guys set up to handle scaling this up when it takes off? I think the idea in itself has a lot of promise. It's nothing revolutionary imo, but it does a lot of stuff better than most hosting sites, and it's a good vision for what it does. A bit snazzier than your standard phpNuke/modified eqDKP systems, and the social aspect is pretty nice.
Hope your security is up to snuff (I imagine you're taking it seriously), because I imagine China is going to have fun with your site once you 'take off.' I haven't signed up for an account yet so I don't know if you're doing this already, but you may want to recommend that people use a UNIQUE password unrelated to their MMO password. Common sense for 'most of us,' but I promise some people will do it. If you ever have to store player IDs/emails for spidering purposes (I'm not sure how the other MMOs work), having a matching password would just be the other half of the key and make you a honey-pot for China, etc. (I guess this also ties into concern #1... but you'd have to be pretty stupid to exploit this

) I imagine you're also going to salt/hash passwords so that'll be secure, so maybe you're not too worried about it outside of MITM?
Anyway, I wish you guys success and I'm sure you've thought of most of this ^ already.
PS. I really like your logo from a design standpoint

. Your site is also very clean and simple- keep it that way! It's going to be interesting to see what this becomes!