I have been getting a few mails concerning the lack of zobrist keys and transposition table. I do know I should implement these soon. For me it is a rather big step though since hash tables can be tricky, with bugs that are both extremely annoying and hard to find.
I have decided to try out null moves, and possibly futility pruning, before going into the hash table swamp.
But do not worry, the zobrist keys and hash tables will come. I am just putting it off for a little bit more. :)