It's unlikely to be as little as the Super Slim at this stage, but similar levels to the Slim are possible. If it needed much more then it would be larger as it would need more cooling.
yeah the slim pulls roughly 70 watts playing fifa 14 which is down from 200 watts in a gen 1 ps3.
IF the ps4 can get to 100watts id be very surprised especially with it running 8 gigs of ram and a super charged 7000 series gpu and a 8 core cpu. but who knows as its all on smaller die's so it may get below 100.
if it does thats going to be a very cool running platform and may explain the smaller case size that the xbone, although they are 90% the same gpu/cpu so id have expected similar heat issues but who knows on what ms have done.