You may well be correct. The little bump that I saw may well be GPU miners taking advantage of the good Bitcoin price at the moment.
Funny you say that. I am a really small time miner and mostly a lurker here, but I shut off all my stuff after the reward halving and waiting for my (BFL) ASIC hardware, but seeing BTC at $25 I turned my GPUs back on and trying to scrounge together more GPU mining hardware to run until difficulty skyrockets. I would guess I am not the only one.