your answers could help me on my research project

I really want to know when they come out. I looked on both the websites but i didn’t see nething(or maybe i overlooked it). Anyway I would really appreciate if you could help me. THanx!

Hey guys. i was just wondering the other day whether purchasing a ps3 or not is the best idea. sure ps3 is great and everything but im worried that the ps4 will be released shortly after i get the ps3 meaning it will be waste of my money. I really dont wana waste my money please help me out with this guys