Onyxia's Last Expansion?

Hello everyone,

I was wondering about the expansions of this server, will WOTLK be the last expansion added?
Or it will continue with others like Cataclysm, end so on?

Thank you.

There is also a Realm with MoP running, because "alot" People asked for it. Look at how many people play there at peak time. I get the thought that on some point one have to think of how further expansion can and should be included. But currently there is no Playerbase for it.