Communicating with readers will be the best way to make blog interactive. This will be kind of online support provided to readers. This may help in resolving readers queries faster rather than commenting and replying to comments.
For this online support option I found Googles very good option Google Talk chatback. For this we just required Google account which already every one has.

When visitors visit your site, they’ll see a badge like the one on the right showing your online status (available, busy, offline) and, if you’re available, they can just click and start chatting. Chatback uses the web-based Google Talk Gadget so your visitors don’t need to download anything. It opens in a new window so they can keep chatting with you even if they browse to other pages.

Of course, chatback isn’t just for blogs. You can use it on any web page that you can add HTML content to. To get started, visit the chatback start page . (This is also linked from the Google Talk homepage.) Then just copy the provided HTML snippet to your web site. Visitors will then see a badge on your site indicating your availability, and can click to start a chat with you. If there’s a time when you don’t want to be distracted, just set your online status to “busy” and visitors won’t be able to chat with you until you change your status back to “available.”

Tags: free Live chat, google chatback, interactive blog, online support