You probably already know that the 11th house deals with hopes, wishes and goals. It also has to do with friendships, and our relationships with groups. To me, this house has had a lot to do with accepting help and advice from mentors much older than myself.
You probably have many interests, and have a great need to learn, but you settle too often for just basic information in many subjects rather than focusing on one in particular. You also have a problem with being easily distracted when something more interesting catches your attention. The main problem with this placement (especially if your Mercury is in Gemini?) is that you may spend time talking or thinking about all the things you want to do rather than actually doing them.
Yes, it is a good place for Mercury. You will have many opportunities come your way, along with persons or groups who will be willing to help you along with your goals. With your placement, and from what you've said elsewhere on this section, I see an aptitude for math which you may not be aware of yet. In particular, I see a talent for accounting, statistics, or a career which would need strategic thinking.
It's very important for you to consider all the aspects Mercury makes to other planets, and in what house those planets reside... with an 11th Mercury, and being a Gemini, does it aspect your ascendant and midheaven?