This piece of news is generally something we would report on, but with the huge amount of debate, complaints and full blown arguments I feel that it is news that needs to be put out there.
Speaking at the E3 roundtable interview Bethesda's Pete Hines said that creating a game of such a high complexity and full interactivity naturally requires some compromise. In this case that compromise is graphical clout.
"Everything that we do is a balance," Hines said, "We could make the best looking game possible, but we dial some of that back in order to allow for all of these other things."
This is fully expected by many long term fans, with the game apparently offering 400+ hours of gameplay, and with even the lead developer not seeing everything that is out in the wastelands it is a given that sacrifices will be made to give the fans such an expansive title to lose themselves in.
Also as other places have pointed out, bleeding edge graphics do not a good game make. The Order: 1886 made this very apparent moving from a game to almost becoming an interactive movie.
In conclusion, many of the people throwing a fit about the graphics have clearly not grasped what the aim actually is for Fallout 4. Either that or they just have not seen this comparison of screenshots gallery kindly compiled by Imgur user Nukeclears which make the graphical changes between Fallout 3 and 4 abundantly clear!