When even mobile browsers have JavaScript, is it really necessary to consider potential script-free users?
My position:
I browse with NoScript, so if I come on your site it will be without benefit of Javascript. I don't expect the full user experience.
What I want, before turning on JS, is to be assured that you're reasonably competent and not malicious, and that I actually want what you're using JS for.
This means that, if you actually want me to use your site, you should allow me to look around, using links. (If I see a site that's totally useless without Javascript, I generally think the designers were incompetent.) You should let me know what sort of functionality I'll get from enabling Javascript, and you should present the site in a legitimate-seeming way.
I don't think that's too much to ask.