What do we think of these questions? Are they on-topic for BCG.SE? Or if they are on-topic, are they a good fit for the SE format?
I would say that simple definitional questions are not appropriate for a StackExchange site. Either you have one question for each term you want defined, and thus have them scattered all over and hard to find, or you have one big question for all terms in a particular game. In the latter case, you either do a "one term per answer", in which voting isn't particularly useful, or you ask for a single complete answer, in which case that one answer is essentially equivalent to a wiki page out of its native habitat.
Simply defining terms is best left for a wiki (in the case of the specific question referred to above, Wikipedia seems to have a great article on it), or some sort of glossary of terms for that game, but not well suited to a question and answer site.
A question and answer site is for answering questions that aren't adequately answered by an obvious Google search, or referring to a reference work for the topic in question. It's for situations that aren't covered by existing references, or are covered but the information might be hard to find or expressed unclearly. A question and answer site is good for clarifying a concept, or learning how it applies to a particular situation, not simply defining it.
edit to add This doesn't mean that I think we should close every easily Googlable question. But I think that we should try and avoid creating lots of "What is [x term] in [y game]" questions, or questions on basic strategy that are already well covered elsewhere, especially during the beta, as StackExchange doesn't make a very good glossary or comprehensive strategy guide.
I answered a similarly short formulaic question here.
The answer can be found elsewhere, but buried away in horrible forums covered in advertising (remember life before SE?!). Perhaps there is something to be said for having them in a clearer format here. Moreover, it's possibly useful to see them suggested when writing related questions, or in the related sidebar.
Also I'm not sure people are trying the game the system, these type of questions never generate a lot of rep for the OP.
Lastly, these questions could be useful in bringing in search traffic.
The poor quality of the, usually short, questions is an issue though.
Either way, perhaps we should watch for down-votes and see what the community thinks?