According to an interview with James Armstrong, VP SCEE, (CEO SCE Spain+Portugal) on 3djuegos, the PS4 may not have graphics better than the PS3.
As stated in the interview, Armstrong does not think that the PS4 will have graphics that are “a lot better graphics than the PS3 currently offered”. He believes Sony’s aim in the next generation is to make games more accessible – especially for women.
For the record, Armstrong says that there’s still a lot of life left on the PS3. In my opinion this is true. I feel as if people will still be playing on the PS3 for many years to come.PS4 Won't Have Better Graphics Than The PS3?,