It really depends on what's being offered.
I didn't blink with the PS3 at $599, because I'm apparently a sucker. I couldn't resists PS1/PS2/DVD/CD/Blu-Ray features, HDMI, wifi, card readers, bluetooth, and all that jazz back in 2006. It worked out for me, though, because the PS3 is easily my most played console.
Nowadays... a $599 console would need to offer some neat hardware feature above and beyond what $399 boxes are doing. Superb BC would probably make me consider it, or, I dunno, some VR perk. I'm expecting $499.