I strongly, and whole-heartedly, recommend it for everyone. Particularly if you've had back problems or surgery. However, talk to the teacher before the class, or get some one-to-one sessions with a trainer, to get tips on modifying certain exercises for your particular situation.
I have been doing pilates exercises for a number of years (even before it became fashionable and in every health club) and it has made a world of difference. I no longer have lower back problems and my posture has improved. As for the running, I feel that I'm stronger and more stable because of it. An additional bonus of pilates classes is that they are quite relaxing (in a weird kinda way!) because the movements are slow and controlled and you really have to focused on what you are doing. Always feel great at the end of any class!
Enjoy!