Do Users Take Product Tours?

Product tours have become very popular in recent times. It's also used here on StackExchange. I personally mostly skip the 'Take a 2 min Tour' notifications or link.

So I'm wondering; based on research/ statistics anyone known may have or have done; how much do users really take the tours? Do most people find them annoying? Are they really worth it?

EDIT

I'll try and be more specific. I'm mostly referring to web applications and web portals, such as this StackExchange's landing page. And within some content management systems eg. Wordpress - where some new plugins come with a 'Welcome to Application 2.0! Take a quick tour to find out our new features'. These tours usually come in form of pop-ups with buttons that lead you to the new feature and the next feature after that, showing more information about said feature, all within the same page. They also allow you to skip the tour and continue on your normal browsing. Facebook has used them on several occasions in the Facebook Pages when showing Admins the changes they have implemented. This is a simple example.

I'm not asking for a specific use-case, just generally. They are a trend and I'm wondering whether people do them just for 'fashion' or whether anyone has had real positive results with users taking tours on their websites/ application or whether they just annoy people.

I guess my question is, has anyone been successful/ unsuccessful with this kind of product tours that can share their experience?