I've been drafting new versions of the Konstantin Stanislavski and related pages (the 'system', the studios, plays he directed, specific productions), which I hope to release into the mainspace soon (the introduction and most of the biography in that article as it currently stands is by me). I've also written a fair amount of the Bertolt Brecht article (the intro, much of the biography that has citatons, the chronology of plays, the bibliography) and some of the related theory-practice articles. I'm also developing a major article on greek tragedy (the Theatre of ancient Greece article is full of inaccuracies at present).
I also dabble in the philosophical terminology of Deleuze and Guattari, which seems to me to be ideal for an encyclopedia, as it's often quite dense. I'm particularly interested in how their semiotics is articulated with Foucault and Negri's concepts.
I dabble in other related articles - tragedy, drama, etc. I have a tendency to spread my focus too widely, which means that it takes a long time before I "complete" articles. Recently I've added a fair amount to the August Strindberg article. I've been trying to clean-up the Expressionism article too.
I'm planning to attend the British Library editathon on Saturday, 4th June, to see what material on drama they have that might be added to Wikipedia.
Some of my contributions are detailed here.
Any comments are welcome on my talk page.