I took a two month vacation from WoW and played SWTOR.
Upon returning to WoW and starting anew on a different server type and faction and a PVP focus, I found that my eyes were straining just trying to read the chat window and navigating the onscreen map looking for quest givers and quest returns. It's going to take me about a week to adjust my eyes to tolerate the hazy graphics resolution.
Even though in my humble opinion, WoW is superior to SWTOR in just about every way in terms of gameplay, the graphics engine is showing its age. Blizzard could get do the impossible by pleasing everybody in the way of gameplay/balance/endgame/PvP/story/etc. but when the graphics physically annoy eyes accustomed to higher quality graphics from just about any other game released in the last two years, new players will not want to play the game.
Sure Blizzard can make graphical tweeks every expansion and improve some things, but there are only so many face-lifts that one can endure before looking like a cat or fish woman.