I think the real question is which group is larger: the customers I'll gain by enabling a feature that requires JavaScript or the customers I'll lose because they're unable to view a feature that requires JavaScript.
According to developer.yahoo.com[1],
> After crunching the numbers, we found a consistent rate of JavaScript-disabled requests hovering around 1% of the actual visitor traffic[...].
I work for a medium sized company that version tests almost every change we make, and in the end the version that wins is the feature with the higher conversion rate.
Conversion rate is a limited metric. It misses the entire concept of word-of-mouth. Conversion rate can't measure people who don't show up in the first place.
I expect NoScript users to be more sophisticated "power users" - the kind of users that regular users go to for advice. If they aren't using your site then they will never recommend it to their more naive and more easily converted friends.
I completely agree, but if a version test wins by more than a few percentage points, it usually makes sense to implement the feature even if it does make the page inaccessible to 1% of users.
According to developer.yahoo.com[1],
> After crunching the numbers, we found a consistent rate of JavaScript-disabled requests hovering around 1% of the actual visitor traffic[...].
I work for a medium sized company that version tests almost every change we make, and in the end the version that wins is the feature with the higher conversion rate.
[1] http://developer.yahoo.com/blogs/ydn/many-users-javascript-d...