I have been studying Togakure Ryu Ninjutsu for about three years now and this has led me to explore more of what budo has to offer. I have read much on Morihei Ueshiba (Stevens) and the origins of Aikido and Aikibujutsu.
I dont really know what the reputation of Ninjutsuka is amongst Aikidoka but the way my Sensai teaches seems similar to more of the Aiki principles inherent to Aikido and less then the linear and aggressive aspects of some Karate Ryu. What I mean by this is that much of the instruction is focused on flow, harmony, and conflict resolution rather then more destructive principals I have seen other Ninjutsu instructors emphasis. We train in falling and rolling skills (but likely not to the extent of Aikido!), and work to develop our technique from the center and as relaxed as possible. Taijutsu we call it. Moving from the body. When I try to muscle a technique (usually against a larger uke) not much happens, however, when I'm really present and just flow with the uke; its magic!
Just wanted to share some thoughts on this. I will be poking around in here, reading and learning. Im looking forward to experiencing Aikido more directly this summer. I imagine the two arts would just augment each other.