it may improve interactivity between hubpages and people visiting hubs if an optional email address column is added in comments capsule. Some of the visitors need answers to their questions asked using comment capsules. Hubber may reply the question by sending e-mail to visitor. It will help improve credibility of hubpages.

We generally reply to questions in comments by adding the answer in a comment, so that everyone who visits can see the answer, as well as the question.

Posting your email address at forums, blog comments or in fact anywhere on the world wide web results in getting more spam than you could ever hope for.

Spammers harvest emails with automated bots.

Thanks inspirepub & darkside for comments. I had only consideration that people usually leave comments (questions) and forget but if they are really serious they may get an answer  directly by the hubber and this may benefit hubpages in terms of responsiveness and reliability. Anyways, your concerns are also valid.

How much more reliable and responsive can you get than answering someone's comment with a comment? 

frank2much wrote:

I had only consideration that people usually leave comments (questions) and forget but if they are really serious they may get an answer  directly by the hubber and this may benefit hubpages in terms of responsiveness and reliability.

I think a lot of non-HP members leave questions and never come back for a response, but I still answer any questions in the hub's comment box. If they really want the answer, they'd come back to check it out. In the mean time, they may have found the answer to their question somewhere else, which is why they may not return.

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