I think that's a great policy. I try to do the same. I check e-mail every day at least once and I'll take an hour of the day and spend it responding to e-mails.

I admit that responding quickly to readers is something I really believe in, but struggle with. Just last week I went through two weeks worth of calls and e-mails. In all, I believed I called and wrote about 75 people. Usually my line for people sending me thoughts on how they hate what my city's politicians are doing is by telling them that I "thank them for their interest in my story" and I give them my usual on how they can voice their opinions: online discussion board I set up, comments on my online stories and letters to the editor. I really try to be good about responding quickly - but each day I receive between 5 and 20 messages. If I write about a really controversial item (usually every other week given my beat) I can get up to 50 messages on just one story. But, I'm trying to get better - I put a flag on e-mails I need to respond to and I write down on a message pad every voicemail received (which I highlight when I've called them back). Gene, I agree with you about how important this is - every time I've called or e-mailed someone back they are happy that I took the time and they usually (even if they don't like the subject I wrote about) leave with trusting me even more because they can ask me more questions and understand my unbiased approach to my stories after talking with me about my stories.

I try to acknowledge most e-mails within a day or so.
My editors advised staff not to explain how we go about covering stories. For the most part, I usually write, "Thank you for your concern" as an acknowledgement.
Sometimes readers have simple requests, such as a phone number or e-mail address of a person whom I've mentioned in a story.
On occasion, some readers, especially those with strong political views, can be nasty. I frequently forward their remarks to my editors.

I respond to emails. It's a good policy.  Why wouldn't I?  Like someone above said, reporters are like salesmen.  We need to sell our writing.  Replying to a reader makes them feel special and encourages them to read more often.