I'd have to get comments first since I seem to be the blogger that writes uncommentable posts. But I'd say to visit the blogs of the people who are commenting at your blog and if you really like the blog subscribe to it.
Happy to get to know that there are bloggers who really get to notice as who had commented on them and do wish to give a thanks for spending time........ wish you a long way! my blog is : http://pavithranluv.blogspot.com http://wafesu.wordpress.com
I'm not sure if you need to reward commenters. I don't like getting comments just for the sake of getting comments, that's meaningless and subsequently, it is meaningless for me to just try to write something on their blog in return. That's hardly better than spam!
Having said that, I generally reply to the comments I get on my blog and often create discussion there.
Here's a tip, if you want to get true comments on your blog, leave your posts open for continued discussion. Finish a post with a question or an open-ended point that leads to commentary. It's much more effective and rewarding than asking for comments and then "returning the favour".
These things can be implemented >> Visiting their blogs and commenting >> Tweeting their posts >> Putting a top commentors gadget on your blog >> Giving free ad space for commentors >> Implemeting commnet luv www.commmentluv.com